NATIONAL SEMINAR ON SCIENCE FOR SUSTAINABLE DEVELOPMENT 25th & 26th September, 2020
ABSTRACT BOOK
Organised By Department of Chemistry B. Borooah College, Guwahati, Assam, India
In Collaboration With Assam Science Technology and Environment Council Department of Science & Technology Govt. of Assam, Guwahati, Assam, India
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Editors:
Dr. Diganta Choudhury Dr. Apurba Kalita Dr. Anupal Gogoi
National Seminar on Science for Sustainable Development, SSD-2020
MADHABDEV UNIVERSITY (A State University established under the Assam Act No. XXXV of 2017) Narayanpur, P.O. Dikrong-784164, Dist. Lakhimpur, Assam ______
Prof. (Dr.) Dibakar Chandra Deka M.Sc., M.Tech., Ph.D., DTIT, D.Sc., FRSC
Vice-Chancellor
Message
It gives me immense pleasure to learn that the Department of Chemistry, B. Borooah College, Guwahati completed its 25 years of PG Program in the year 2019. On the occasion the department started organizing a National Seminar as an annual event, and the 2nd one on a contemporary topic ‘Science for Sustainable Development (SSD-2020): Climate Change’ is being held on 25th & 26th September 2020. I extent my heartiest congratulation to the Department for its achievements and appreciate college authority for its support to the Department of Chemistry in its path of growth. The past and present faculties and the staff of the department deserve special mention for their untiring efforts in the last 26 years, without whose supports the department could not have achieved the present level of status. As a faculty of chemistry in Gauhati University, I did keenly notice the Growth of the Department of Chemistry in B Borooah College. In spite of constraints in faculty recruitments and the space for infrastructure development, the Department has successfully conducted not only PG Program but also UG Program in Chemistry to achieve prominence. In fact, B Borooah College has been the most sought-after destination for UG chemistry aspirants in the last couple of years. This has been possible because of the untiring dedication and hard-work of the department and support extended by the college authority. The COVID-19 pandemic is even unable to deactivate their spirit. I wish the seminar a grand success, and the Department of Chemistry, B Borooah College would continue to grow undeterred in coming years to achieve new heights.
(D. C. Deka)
National Seminar on Science for Sustainable Development, SSD-2020
National Seminar on Science for Sustainable Development, SSD-2020
MESSAGE
It gives me immense pleasure that the Department of Chemistry, B. Borooah College is organizing a National Seminar on "Science for Sustainable Development" on 25 and 26 September, 2020 in association with Assam Science Technology and Environment Council (ASTEC). The Seminar which was slated to be in offline mode in March 2020 has to be postponed because of the current pandemic situation and now is being organised in the virtual mode. The theme of the seminar “Science for Sustainable Development” reflects aptly the need of the hour as each and every one of us is concerned at the way development has impacted on the environment.
I am extremely delighted to welcome all distinguished participants and hope they have active and fruitful deliberations in this seminar. I sincerely hope that the Seminar will be a successful one.
(Dr. Satyendra Nath Barman) Principal B. Borooah College Date: 23rd Sept 2020 Guwahati
National Seminar on Science for Sustainable Development, SSD-2020
From the Organizer’s Desk…
The National Seminar on Science and Sustainable Development (SSD-2020), hosted by Department of Chemistry, B.Borooah College, Guwahati, provides an excellent forum for the sharing of ideas, presentation ofresearch findings, and discussion of professional issues relevant to Sustainability Science. The aim of this seminar is to promote national collaboration in Sustainable chemistry and its related disciplines. All abstracts were reviewed by members of the SSD2020 SteeringCommittee for rating of abstract quality and presentation content.
I would like to thank the scientific community for contributing to the success of thisNational Conference on Sustainable Development and look forward tohaving the opportunity to showcase and disseminate your research.
Global change has created enormous challenges for humanity. With increase in the world's population global energy requirements will also continue to increase. The ecological problems caused by human economic activity are becoming worse and taking on global dimensions. Climate change, loss of forest cover and ozone-layer depletion, are important examples. At the same timein many developing countries, the social conditions continue to decline with a large percentage of people living in poverty, without sufficient food or adequate educational opportunities. Henceforth, we must turn our efforts towards the task of environmental protection and development so that our country is capable of achieving its full economic potential while at the same time enhancing its resource base.
Sustainability as a strategic aim, involves optimizing the interactions between nature, society, and the economy, in accordance with ecological criteria.The‘needs’of our future generation that are addressed by Sustainable development, goes beyond simply material needs and includes values, relationships, freedom to think, act, and participate, all amounting to sustainable living- morally and spiritually. The concerns are for preserving and enhancing the environment and its biodiversity and to ensure human rights in a healthy and productive world.
I hope that this seminar will help stimulate innovation across all sectors of our society and encourage our young scientists to design and discover new chemicals and production processes that will provide increased performance while protecting and enhancing human health and the environment.
I would like to take this opportunity to thank the faculty and student members of the Department of Chemistry, B.Borooah College, who have worked as a team to make this national seminar a memorable event.
Dr.Sutopa Raichaudhury Working President, SSD-2020 Head, Department of Chemistry B. Borooah College
National Seminar on Science for Sustainable Development, SSD-2020
Contents
Sl No Author Title
Prof. Bhupendra Nath Key Note Address Goswami
Abstract of Invited Lectures
IL-1 Prof Ghanashyam Bez Development of Environmentally Benign Approach in the synthesis of biologically relevant heterocycles
IL-2 Prof Ramesh Chandra Modelling the Sustainable Catalysts Using Hybrid QM/MM Deka Method
IL-3 Prof Prodeep Phukan Surface functionalized magnetic nanoparticles for catalytic applications
Abstract of Short Invited Lectures
SIL-1 Dr. Bipul Sarma Engineering Cocrystals to Improve Stability and Pharmacokinetic Properties of Fickle Drugs: A Combination
Therapy SIL-2 Unexplored Chemistry of Beryllium Dr. Ankur Kanti Guha SIL-3 Low Molecular Weight Gelator based Metallogels for Dr. Debajit Sarma Environmental Remediation
SIL-4 Dr. Sanjeev P. Revisiting the fluoride binding ability of some old receptors in Mahanta aqueous medium by Cu(II) complexation strategy SIL-5 Dr. Sasanka Deka Use of nanostructured materials for sustainable energy
SIL-6 Dr. Dhruba Jyoti Donor-Acceptor (DA) type Oligomers for Organic Photovoltaics Kalita : A DFT/TDDFT Study
SIL-7 Dr. Parikshit Gogoi Biomass conversion to fuel and chemicals with redox couple catalysts
SIL-8 Dr. Sagar Sharma Computational studies on organic semiconductors based on diketopyrrolopyrroles and naphthalenediimides SIL-9 Dr. Jyotirmoy Sarma Effect of sea water on the flocculation of iron ore tailings and fines and beneficiation studies: An overview Abstract of Oral Presentation OP-1 Rinki Moni Kalita Synthesis of ruthenium complexes and donor properties of N- heterocyclic rings in complexes
National Seminar on Science for Sustainable Development, SSD-2020
OP-2 Rahul Kumar Sarma Electronic Properties of Ruthenium Complexes Having Baruah Vinyl Imidazole Ligand OP-3 Sarojmoni Kalita Dyes Intercalated on Mesoporous Particles as Sensors
OP-4 Dr. Ashim Baishya N-Heterocyclic Carbene Magnesium Chemistry: Synthesis and Catalysis
OP-5 Pankaj Saikia Analysis of dietary fibre of some indigenous vegetables of Assam
OP-6 Shahnaz S. Rohman Ultra-Weak Metal-Metal Bonding: Does a Beryllium-Beryllium Triple Bond Exist? OP-7 Nikita Chakraborty Base Promoted Synthesis of Quinoline-4(1H)-thiones and itsThiocarbonylDirected Regiospecific C-H/S-H Annulation with Alkynes OP-8 Basanta Kumar Das Trace Element Contamination and Human Health Risk Assessment in Drinking Water of a Small Town of Lower Assam OP-9 PrashuryaPritamMudoi Evidence of protonation induced intra-molecular metal-to-metal
charge transfer in a highly symmetric cyanido bridged {Fe2Ni2} molecular square
OP-10 Susma Das A facile green synthetic strategy forpyrazolo[1,5- a]pyrimidineswith potent anti-bacterialproperties OP-11 Abhishek Borborah Naked eye detection of Nitrophenol vapours via band gap engineering in Perylene HOFs OP-12 Saad Zafar Remaking the way from waste: a sustainable strategyof chitosan- polybenzoxazine-sulfur composite beads for heavy metal removal from waterand crude oil spill remediation
OP-13 Chiranjita Goswami Highly stable nanostructured Co3O4-CeO2/C hybrid as an efficient electrocatalyst for oxygen reduction reaction
OP-14 Swati Basak Electrocatalytic oxidation of water by a copper complex containing Histidine derived ligand OP-15 Critiquing Sustainability: Migratory Pathogens and Conflict of Manabendra Sarma Interests in Context OP-16 Dr. Satyabrata Baruah Trends of Higher Education in a Sustainable Future
OP-17 Rajarshi Bayan Hyperbranched Polymer-Supported Graphitic Carbon Nitride Nanodots for Photocatalytic Oxidation and Reduction Reactions OP-18 Dr. Chandan Sharma Why Scientific Education matters to Health and Wellbeing: A Study on Indian Context
National Seminar on Science for Sustainable Development, SSD-2020
OP-19 Tukki Sarkar Ferrocene Appended Novel Iron(III)-Esculetin Complex as a Dual-Pathway Phototheranostic Agent OP-20 Manali Dutta 2,2′-bibenzimidazole based Ruthenium(II) Precatalysts for Oxidation of Alkenes: Breaking the Barrier with Cooperativity OP-21 Parmeeta Borthakur Synthesis and characterization of Cyclometalated iridium complex possessing carbazole containing dendritic ligands OP-22 Priyankamoni Saikia Perovskite-based Photocatalyst
OP-23 J.K.R. Deka Conformation control of N-methyl-N,N'-diacylhydrazines by noncovalent carbon bonding OP-24 Sudhangshu Priya ExploitingCu(II)-Fluoride Interaction with Receptor for Bharati Sensitive and Selective Recognition of Aqueous Fluoride
OP-25 Prabhat Chandra Climate Change and Its Impact on Biodiversity Choudhury OP-26 Dr. Dhanjit Deka Watershed Management: A Case Study of Jonai Korong Watershed, North East India OP-27 Raktim Abha Saikia Room Temperature Copper-Catalyzed N-Arylations of Hydantoins employingDiaryliodonium Salts
OP-28 Debabrat Pathak Base Mediated Hydride Eliminating Benzyl Alcohol Oxidation Supported Over Microporous Organic Polymer OP-29 Manoj Kumar Das A Study on Government Measures Towards Street Vending as a Sustainable Livelihood Strategy in India at the Advent of Covid -19
OP-30 Hemrupa Kuilya Homogeneous Catalytic Water Oxidation by Nickel Complex with redox active Oxime ligand
OP-31 Jyotish Nath Spatiotemporal proteome mapping for organelle- communications using two orthogonal protein labeling & isolation methods
OP-32 Pranjal Das Homogeneous Electrocatalytic Water Oxidation by Copper (II) Complex with Redox Active Ligand in Neutral Phosphate Buffer Abstract of Poster Presentations
PP-1 ChayanikaKashyap Exploring the Reactivity of Carbene Supported DiboraanthraceneTowardsDihydrogen Activation
PP-2 Sheikh Abdullah Photophysical studies of three green fluorescent protein chromophore analogs
PP-3 Nabajit Barman Study on Ambient Air Quality at Guwahati, Assam, India
National Seminar on Science for Sustainable Development, SSD-2020
PP-4 Dona Deb Removal of Fluoride from Aqueous Solution Using Fish Scale
PP-5 Kaushiki Deka Organic Manure Formulation Using Eri-Muga,Cow And Poultry Excreta
PP-6 Hiranya Gogoi Label-free Sensing of A basic DNA using Pyrenylamido Triazolyl Aromatic Amino Acid Scaffold as AIE probe
PP-7 Bidisha Bora Mn(III) Porphyrins For Photo-induced in vitro Anticancer Activity PP-8 Namisha Das Structurally characterized Cu(II)-flavonoid complexes with potential biological application
PP-9 Surajit Kalita The Preparatory Choreography During O2 Binding and Origins of the Necessity for Two Protonation Pathways in the Catalytic Cycle of P450
PP-10 Amal Das Unconventional Supramolecular Contacts involving nitrile in Pyridine based Ni(II) and Zn(II) Coordination Compounds: Antiproliferative Evaluation and Theoretical Studies PP-11 Nilotpal Borah Anion recognition aptitude of a pair of non-symmetrical tripodal receptor in both solid state and solution phase
PP-12 Rashmi Chetry Pd3Cu0.5Ni0.5 Nanowire Networks Stabilized on Carbontowards Boosting Dioxygen Reduction in Alkaline Electrolyte
PP-13 Suranjana Patowary Interfacial CuCo/CuOx-Co3O4/C Nanohybrids as Highly Stable Electrocatalysts for Oxygen Reduction Reaction
PP-14 Atrayee Banaspati Synthesis, Structure and Photo-triggered in vitro anticancer activity of Ni(II) complexes of curcumin PP-15 Indrani Baruah Structural and Functional Changes of Protein β-Lactoglobulin Under Thermal and Electrical Processing Conditions
PP-16 Sourav Kalita Effective modulation against amyloid aggregation of hIAPP using modified stapled peptides PP-17 Himanshu Sharma Control Nucleation and Crystal growth of Drugs in Organogels
PP-18 Pubalee Sarmah Reactivity of 9-anilinoacridine derivatives as potent anticancer agents: A DFRT approach PP-19 Rajan Kumar A Review on Polymer and Sulphur (S) Chemistry
PP-20 Bilash Jyoti Gogoi Electrical Conductivity Studies of PVA-PVP-Na2SO4Solid Polymer Electrolytesfor Application in Solid State Battery
National Seminar on Science for Sustainable Development, SSD-2020
NATIONAL SEMINAR ON SCIENCE FOR SUSTAINABLE DEVELOPMENT (SSD-2020) 25th & 26th September, 2020
Time Schedule
Day 1 25th September
Inaugural Session
9.30-10.00 Joining the Seminar on Zoom 10.00-10.05 Welcome Address 10.05-10.15 Inaugural Lecture Dr. Arup Kumar Misra Director, Assam Science Technology & Environment Council (ASTEC) 10.15-10.25 Speech by Guest of Honour Prof. Dibakar Chandra Deka Honourable Vice Chancellor, Madhabdev University 10.25-10.55 Key Note Address Prof. Bhupendra Nath Goswami SERB Distinguished Fellow, Department of Physics, Cotton University 10.55-11.00 Vote of thanks Break Session 1
11.25-11.30 Chair: Prof. Dibakar Chandra Deka Honourable Vice Chancellor, Madhabdev University 11.30-12.00 IL1: Prof. Ghanashyam Bez Department of Chemistry, NEHU Shillong 12.00-12.30 IL2: Prof. Ramesh Chandra Deka Department of Chemical Sciences, Tezpur University
12.30-13.00 IL3: Prof. Prodeep Phukan Department of Chemistry, Gauhati University Lunch Break
Session 2
14.25-14.30 Chair: Dr. Saroj Kumar Bhattacharyya Mark Wainwright Analytical Centre, University of New South Wales, Australia 14.30-14.45 SIL 1: Dr. Bipul Sarma Department of Chemcal Sciences, Tezpur University
National Seminar on Science for Sustainable Development, SSD-2020
14.45-15.00 SIL 2: Dr. Ankur Kanti Guha Department of Chemistry, Cotton University 15.00-15.10 OP 1: Rinki Moni Kalita Research Scholar, Department of Chemistry, Gauhati University 15.10-15.20 OP 2: Rahul Kumar Sarma Baruah Research Scholar, Department of Applied Sciences, Gauhati University 15.20-15.30 OP 3: Sarojmoni Kalita Research Scholar, Department of Chemistry, Gauhati University 15.30-15.40 OP 4: Dr. Ashim Baishya School of Chemical Sciences, NISER, Bhubaneswar 15.40-15.50 OP 5: Dr Pankaj Saikia Assistant Professor, Department of Chemistry, Tinsukia College 15.50-16.00 OP 6: Shahnaz S. Rohman Research Scholar, Department of Chemistry, Cotton University End of Day 1 Day 2 26th September Session 3
9.30 Joining the Seminar on Zoom 9.55-10.00 Chair: Dr. Manjit Bhattacharyya Department of Chemistry, Cotton University 10.00-10.15 SIL 3: Dr. Debajit Sarma Department of Chemistry, IIT Patna 10.15-10.30 SIL 4: Dr. Sanjeev Pran Mahanta Department of Chemcal Sciences, Tezpur University 10.30-10.40 OP 7: Nikita Chakraborty Research Scholar, Department of Chemistry, IIT Guwahati 10.40-10.50 OP 8: Basanta Kumar Das Department of Chemistry, Kokrajhar Govt. College 10.50-11.00 OP 9: Prashurya Pritam Mudoi Research Scholar, Department of Chemical Science, Tezpur University 11.00-11.10 OP 10: Susma Das Research Scholar, Department of Chemical Science, Assam Don Bosco University 11.10-11.20 OP 11: Abhishek Borborah Research Scholar, Department of Chemical Sciences, Tezpur University 11.20-11.30 OP 12: Saad Zafar Research scholar, Department of Chemistry, Shiv Nadar University Break Session 4
11.40-11.45 Chair: Dr. Jaideep Baruah, Head i/c, Environment Division, ASTEC
National Seminar on Science for Sustainable Development, SSD-2020
11.45-12.00 SIL 5: Dr. Sasanka Deka Department of Chemistry, Delhi University 12.00-12.15 SIL 6: Dr. Dhruba Jyoti Kalita Department of Chemistry, Gauhati University 12.15-12.30 SIL 7: Dr. Parikshit Gogoi Department of Chemistry, Nowgong College 12.30-12.40 OP 13: Chiranjita Goswami Research Scholar, Department of Chemical Sciences, Tezpur University 12.40-12.50 OP 14 : Swati Basak Research Scholar, Department of Chemistry, B. Borooah College 12.50-13.00 OP 15: Manabendra Sarma Assistant Professor, Department of English, B. Borooah College 13.00-13.10 OP 16: Dr. Satyabrata Baruah Assistant Professor, Department of Education, B. Borooah College 13.10-13.20 OP 17: Rajarshi Bayan Research Scholar, Department of Chemical Sciences, Tezpur University 13.20-13.30 OP 18: Dr. Chandan Sharma Assistant Professor , Department of Economics, Morigaon College 13.30-13.40 OP 19: Tukki Sarkar Research Scholar, Department of Chemistry, Handique Girls’ College Lunch Break
Session 5
14.25-14.30 Chair: Dr. Rupam Jyoti Sarma Department of Chemistry, Gauhati University 14.30-14.45 SIL 8: Dr. Sagar Sarma Department of Chemistry, Assam Don Bosco University 14.45-15.00 SIL 9: Dr. Jyotirmoy Sarma Department of Chemistry, Kaziranga University 15.00-15.10 OP 20: Manali Dutta Research Scholar, Department of Chemical Sciences Tezpur University 15.10-15.20 OP 21: Parmeeta Borthakur Research Scholar, Department of Chemistry, NEHU, Shillong 15.20-15.30 OP 22: Priyankamoni Saikia Research Scholar, Department of Chemical Sciences, Tezpur University 15.30-15.40 OP 23: Jugal Kishore Rai Deka Research Scholar, Department of Chemistry, Shiv Nadar University 15.40-15.50 OP 24: Sudhangshu Priya Bharati Research Scholar, Department of Chemical Sciences, Tezpur University 15.50-16.00 OP 25: Prabhat Chandra Choudhury Assistant Professor, Department of Chemistry, B.H.College, Howly
National Seminar on Science for Sustainable Development, SSD-2020
16.00-16.10 OP 26: Dr Dhanjit Deka Assistant Professor, Department of Geography, B Borooah College 16.10-16.20 OP 27: Raktim Abha Saikia Research Scholar, Department of Chemical Sciences, Tezpur University 16.20-16.30 OP 28: Debabrat Pathak Research Scholar, Department of Chemical Sciences, Tezpur University 16.30-16.40 OP 29: Manoj Kumar Das Research Scholar, NERIST, Nirjuli, Arunachal Pradesh
16.40-16.50 Valedictory Session
IL: Invited Lecture; SIL: Short Invited Lecture; OP: Oral Presentation
Poster Session on Facebook Page From 25-26, September 2020 https://www.facebook.com/Ssd-2020-100334338481725/
National Seminar on Science for Sustainable Development, SSD-2020
Keynote Address
Climate Emergency: Why need to STOP Denying and ACT Now!
B. N. Goswami
SERB Distinguished Fellow Department of Physics Cotton University Guwahati 781001 Email: [email protected]
The explosive growth of human population on earth over the past two centuries, its greed for consumption of natural resources led to explosive growth of green house gases in the atmosphere unprecedented in the last three million years. The human induced change in the environment has driven the earth’s climate to a ‘tipping point’ and a transition to ‘hothouse earth’ appears inevitable! There is also evidence that the ‘sixth mass extinction’ is accelerating, a reaction of the environment on the vertebrate populations including human. COVID--‐19 is likely to further accelerate it. That is why; the earth’s climate has reached a point where ‘emergency’ treatment is essential. It has to be given ‘ICU’ treatment and no less! Therefore, any attempt at ‘sustainable development’ is an attempt at futility unless we put a STOP on the climate change. With some key players still on denial and the measures taken by others who accept climate change being inadequate due to various compulsions, the prospect of stopping the climate change remains a piped dream. Hence, talks and discussions on ‘sustainable development’ are hypocritical unless cumulative actions of governments to reduce GHG emissions as per Paris agreement are in place.
The talk starts with few examples of anthropogenic change in the environment. A quick introduction to science of climate change and its nonlinearity and complexity indicates that a deterministic prediction is impossible. However, probability of the change can be quantified with high confidence. Therefore, our decisions on response to climate change and on mitigation MUST be based on this probability. We make all decisions based on probability, even on financial markets but when it comes to climate change, we (the Denialists) demand a deterministic number! This is the problem with humans. Therefore, I do not see a great prospect of stopping the climate change.
National Seminar on Science for Sustainable Development, SSD-2020
IL-1
Development of environmentally benign approach in the synthesis of biologically relevant heterocycles
Ghanashyam Bez
Centre for Advanced Studies in Chemistry, Department of Chemistry, North Eastern Hill University, Shillong-793022, India [email protected]
Catalyst and solvent play major role in development of environmentally benign protocol for synthesis. Among the catalyst, enzyme and solid-supported catalysts have played major role in this direction due to their biocompatibility and recyclability respectively. Ironically, many publications claiming to have used catalyst with high recyclability fail to recognize the fact that catalyst preparation steps are often not environmentally benign. Therefore, the use of readily available catalyst is one of the major areas, that we often neglect, must be our thrust to develop truly environmentally protocols. Similarly, solvent-free protocols and protocols using environmentally compatible solvents have found a lot of importance in recent decades; but most report conveniently undermines the use of hazardous organic solventsduring extraction and purification process. In this lecture, some of our efforts along this direction will be presented wherein we have successfully developed biologically relevant heterocycles (Fig 1) using readily available and simple catalyst and environmentally benign processes.1-4
F Figure 1: Biologically relevant heterocycles
References: 1. Pasupuleti, B G; Khongsti, K; Das, B; Bez, G, European Journal of Medicinal Chemistry (2020), 186, 111908. 2. Bihani, M; Bora, P P.; Bez, G; Askari, H, Molecular Diversity (2014), 18(4), 745-757. 3. Bora, P P.; Bihani, M; Bez, G, Journal of Molecular Catalysis B: Enzymatic (2013), 92, 24-33. 4. Bihani, M; Bora, P P.; Bez, G; Askari, H, ACS Sustainable Chemistry & Engineering (2013), 1(4), 440-447. 5. Bihani, M; Bora, P P.; Bez, G; Askari, H, ComptesRendusChimie (2013), 16(5), 419-426.
National Seminar on Science for Sustainable Development, SSD-2020
IL-2
Modelling the Sustainable Catalysts Using Hybrid QM/MM Method
Ramesh Ch. Deka
Department of Chemical Sciences, Tezpur University, Napaam, Tezpur – 784 028, Assam, India
Structure and reactivity of metal oxide catalysts were modelled by combining quantum chemical methods with molecular mechanics. The active sites of catalysts such as zeolites are treated with highly accurate quantum chemical method and the surrounding of the active sites is treated with molecular mechanics force fields. We have used this hybrid QM/MM principle to study the catalytic activity of zeolite catalysts for CO oxidation. By modelling titanium silicalite –I, we have determined the most preferred site for titanium substitution in the material. QM/MM methods have also been found very effective in modelling conversion of lignocellulosic biomass to biofuel and biomaterial production.
National Seminar on Science for Sustainable Development, SSD-2020
IL-3
Surface functionalized magnetic nanoparticles for catalytic applications
Prodeep Phukan
Department of Chemistry, Gauhati University, Guwahati -781014, Assam, India E-mail: [email protected]
Catalysts in nanometer dimensions have significant advantages over other catalyst as the nanoparticles provide a larger number of active sites per unit area [1, 2]. However, recovery of nanoparticles is a major drawback as they cannot be efficiently filtered out of the reaction medium. In this respect, magnetic nanoparticles hold out significant potential as a reusable catalyst as they can be recovered simply by magnetic separation which intern prevents loss of catalyst and increases reusability. This new magnetic catalytic systems offer significant benefits in achieving environmentally friendly organic syntheses aiming towards green and sustainable chemistry.
MAGNET
We have synthesized spinel cobalt ferrite magnetic nanoparticles by a combined sonochemical and co-precipitation technique [3a, b]. Catalytically active metals were incorporated onto the surface of the magnatic nanoparticle with the aid of a linker. The hybrid catalyst was used for various C-C bond forming reactions [3b-h]. The magnetic nanocatalyst was recovered from reaction medium with the aid of a magnet.
Reference
[1] D. Astruc, F. Lu, J. R. Aranzaes, Angew. Chem., Int. Ed. 2005, 44, 7852–7872. [2] M. T. Reetz, M. Maase, Adv. Mater. 1999, 11, 773–777. [3] (a) C. Borgohain, K. K. Senapati, D. Mishra, K. C. Sarma, P. Phukan, Nanoscale, 2010, 2, 2250; (b) K. K. Senapati, C. Borgohain, K. C. Sarma, P. Phukan, J. Mol. Catal. A: Chem., 2011, 346, 111; (c) K. K. Senapati, S. Roy, C. Borgohain, P. Phukan, J. Mol. Catal. A: Chem., 2012, 352, 128; (d) K. K. Senapati, C. Borgohain, P. Phukan, Catal. Sci.Technol., 2012, 2, 2361; (e) S. Roy, K. K. Senapati, P. Phukan, Res. Chem. Intermed.,2015, 41, 5753; (f) M. M. Dutta, K. K. Rajbongshi, P. Phukan, Synth. Commun., 2017, 47, 2330; (g) M. M. Dutta, K. K. Rajbongshi, P. Phukan, Catalysis Communications 2018, 109, 38; (h) M. M. Dutta, H. Talukdar, P. Phukan; Dalton Trans., 2019, 48, 16041.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-1
Engineering Cocrystals to Improve Stability and Pharmacokinetic Properties of Fickle Drugs: A Combination Therapy
Bipul Sarma
Department of Chemical Sciences, Tezpur University, Napaam-784028, Tezpur, Assam, India E-mail: [email protected]
A new drug formulation has significant implication on the biopharmaceutical parameters and treated as crucial step in drug development. The cocrystal engineering approach has been employed to improve phase stability, while retaining the intrinsic bioavailability of the drug molecule. We report the degradation behaviour at stomach acidic pH of the drug Famotidine, a prescription drug used to treat ulcers of the stomach and intestines. As remedy for degradation, three cocrystals were synthesized with xanthine drugs i.e. Theophylline, Caffeine and Theobromine. Stability, solubility and membrane permeation studies suggest enhanced permanence of the cocrystals in experimental conditions and examined structure activity relationships. A mechanistic insight of phase stability exhibited by these cocrystals was examined with the help of UV-Visible, 1H- & 13C-NMR, FT-IR spectroscopy, and single crystal and Powder X-ray diffraction studies and presented. This study can be projected as cocrystal engineering, a viable alternate of development of combination medicines with improved biopharmaceutics properties.
References 1. P. Bora, B. Saikia, B. Sarma, Chem. Eur. J. 2020, 26, 699-710 2. B. Saikia, N. Sultana, T. Kaushik, B. Sarma, Cryst. Growth Des. 2019, 19, 6472-6481 3. R. Khatioda, P. Bora and B. Sarma, Cryst. Growth Des. 2018, 18, 4637-4645. 4. R. Khatioda, B. Saikia, P. J. Das and B. Sarma, CrystEngComm, 2017, 19, 6992-7000 5. B. Saikia, P. Bora, R. Khatioda and B. Sarma, Cryst. Growth Des. 2015, 15, 5593-5603 6. A. V. Trask, W. D. S. Motherwell, W. Jones, Cryst. Growth Des. 2005, 5, 1013–1021
National Seminar on Science for Sustainable Development, SSD-2020
SIL-2
Unexplored Chemistry of Beryllium
Ankur Kanti Guha
Department of Chemistry Cotton University Panbazar, Guwahati, Assam-781001
Beryllium, one of the alkaline earth metal, is very toxic and needs special care to handle for the chemists. Thus, converting it to safer chemicals is very essential which prompted researchers for many years. In doing so, many new safer chemicals containing Beryllium have been developed. Herein, we have designed some Beryllium compounds with unusual chemistry which have never been thought of. We have theoretically designed Beryllium dimers featuring triple bond and have designed one interesting compound where Beryllium itself acts as the stabilizing factor for realizing planar hypercoordinate species.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-3
Low Molecular Weight Gelator based Metallogels for Environmental Remediation
Debajit Sarma
Department of Chemistry, Indian Institute of TechnologyPatna, Bihta-801106, Bihar, India e-mail: [email protected]
Supramolecular gel material is a gift of serendipity, and metal incorporation imparts diverse functional properties. Similar to metal organic frameworks (MOFs), the 3D network structure of the metal organic gels (MOGs) is composed of organic linkers/low molecular weight gelators (LMWGs, molecular weight less than 3000) and metal nodes. Several noncovalent interactions such as hydrogen bonding, hydrophobic, electrostatic and π−π interactions constitute the three dimensional MOG network that contain large amount of immobilized solvents through surface tension.1The MOGs finds its application indrug delivery, environmental remediation, catalysis, light-emitting diodes, nanoelectronics and biomedicine.2We have designed and synthesized a series of nickel and copper metal ions incorporated metal organic gels from bifunctional carboxylic acid/amide-based low molecular weight gelators. These MOGs can be tuned to be a low-temperature precursor of porous spinel oxides (Figure 1) and exhibit impressive water soluble dye adsorption.3Similarly, we have synthesized a porous Mg@DEOAmetallogel (180 m2/g) with 2D sheet morphology that exhibits thixotropic and injectableproperty. The material was found to be an effective (587 mg/g) host matrix for iodine sequestration from solution. This xerogel was applied to efficiently remove rhodamine B from a mixture of dyes with high separation factors through xerogel packed column and as an adsorbent material for CO2. Facile synthesis of thesemetallogels coupled with its excellent sorbent properties underscores its potential in environmental remediation.
Figure1. Pictorial representation of the formation of precursor metallogel, and the subsequent thermal decomposition to spinel.
References
1. Dietrich, D.; Licht, C.; Nuhnen, A.; Höfert, S.-P.; De Laporte, L.; Janiak, C. ACS Appl. Mater. Interfaces2019,11, 19654-19667. 2. Kuosmanen, R.; Rissanen, K.; Sievänen, E.Chem. Soc. Rev.2020,49, 1977-1998. 3. Alam, N.; Sarma, D. ACS Omega 2020,5, 17356-17366.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-4
Revisiting the fluoride binding ability of some old receptors in aqueous medium by Cu(II) complexation strategy
Sanjeev P. Mahanta
Department of Chemical Sciences, Tezpur University, Tezpur 784028, Assam, India E-mail: [email protected]
Prolonged intake of water contaminated with fluoride at concentrations exceeding 1.0 ppm can lead to significant health implications, especially in children and developing embryos. In view of the irreversible and potentially severe forms of fluoride toxicity such as dental and skeletal fluorosis being endemic in at least 25 countries, constructing affordable, remote-access, reliable water- sampling methods for detecting F– contamination are an important goal. In this regard, the recognition of fluoride anion with artificial host with visible optical signal transduction is widely explored domain in host guest chemistry research. The recognition of fluoride ion in aqueous medium is still a serious concern owing to the high enthalpy of hydration offluoride and the low solubility of the artificialhost in aqueous medium. Therefore, the requirement of a protocol for sensing of fluoride ion in aqueous medium using some reported fluoride binding host which shows fluoride affinity only in organic medium is worthwhile. Herein, a transition metal (Cu(II)) mediated strategy for the detection of aqueous fluoride with receptors like pyrrol-2′-yl-quinoxaline, and Schiff base derivatives are explored and demonstrated.The methodology is also validated with the real life samples like groundwater collected from fluoride affected areas and toothpaste extract.
References:
1. Das R., Bharati S. P, Borborah A., Sarma P. J., Das B., Choudhury S., Chakrabarty G., Mahanta S. P., New J. Chem.2018, 42, 3758. 2. Das R., Sarma P. J., Bharati S. P, Borborah A., Mahanta S. P., New J. Chem.2019, 43, 3447.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-5
Use of nanostructured materials for sustainable energy
Sasanka Deka
Department of Chemistry, University of Delhi, North Campus, Delhi-110007 *Corresponding author e-mail: [email protected], [email protected]
Size dependent characteristics of nanoparticles lead to use of these nanomaterials in many technologically important fields, including the field of energy conversion and storage which are much more related to green, sustainable and evolving Sciences. The electrochemical routes to energy storage and electrochemical/photocatalytic routes energy conversion processes have attracted a great deal of research attention in recent years to find sustainable and highly efficient alternative energy as a substitute for exhaustible fossil fuels. As a contribution to this field, we have developed few highly efficient nanostructured materials to convert energy and to store energy electrochemically. We will discuss the development and applications of a few of these materials
(e.g. CuCo2S4, Co3S4, NiCo2O4, g-C3N4, etc.) during the talk.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-6
Donor-Acceptor (DA) type Oligomers for Organic Photovoltaics : A DFT/TDDFT Study
Dr. Dhruba Jyoti Kalita* and Shahnaz Ahmed
Department of Chemistry, Gauhati University, India e-mail: [email protected]
We have designed a series of organic oligomers with Donor- Acceptor approach to study the charge transport. We have studied the structural, charge injection and transport properties employing the Density Functional Theory. We have also exploring the way to tune the electronic properties of the proposed compounds. In this regard, we have designed a series of isoindigo-dithiophenepyrrole based compounds, triphenylamine based organic dyes and BAI based compounds for the fabrication of organic photovoltaics. To fulfill our objectives we have calculated dihedral angles, distortion energies, bond length alteration parameters, band gap values, partial density of states, reorganization energy, charge transfer rates, hopping mobility values and absorption spectra of the compounds. Our study manifests that the absorption properties of our designed compounds are changed by the attachment of substituents and can be tuned according to the requirements. In short, we infer that our designed compounds may act as promising candidates for organic photovoltaics.
Referrences:
1. S. Ahmed and D. J. Kalita, Rational Design of Bay-Annulated Indigo (BAI)-Based Oligomers for Bulk Heterojunction Organic Solar Cells: A Density Functional Theory (DFT) Study, ACS Omega, 2020 (14), 8321-8333 2. S. Ahmed and D. J. Kalita, Charge transport in isoindigo-dithiophenepyrrole based D-A type oligomers: A DFT/TD-DFT study for the fabrication of fullerene-free organic solar cells,J. Chem. Phys., 2018 (149), 234906 3. R. Dutta, S. Ahmed and D. J. Kalita, Theoretical design of new triphenylamine based dyes for the fabrication of DSSCs: A DFT/TD-DFT study,Materials Today Communications, 2020 (22), 100731
National Seminar on Science for Sustainable Development, SSD-2020
SIL-7
Biomass conversion to fuel and chemicals with redox couple catalysts
Parikshit Gogoi
Department of Chemistry, Nowgong College, Nagaon 782001, Assam, India e-mail: [email protected]
The growing energy demand, limited nature of fossil fuels, and environmental impact enhance the search for alternative sustainable fuels and chemicals. The utilization of biomass as alternatives to fossil fuels as a renewable energy source is a promising solution for a more sustainable society. The production of second-generation biofuels from lignocellulosic sources and chemicals from lignin is a primary concern for Industry and academia from a technology- development perspective. Pretreatment of biomass to cellulose for bioethanol production is a vital step of it. For the first time, we developed a simple, effective, and low-temperature (~100 0C) method for the pretreatment of wood chips directly by using a catalytic system of FeCl3/NaNO3. Similarly, selective lignin depolymerization to chemicals enhances the sustainability of downstream processing of biomass in a bio-refinery. The depolymerization of lignin is challenging due to its complicated structural pattern and changes during the process. The redox couple effectively depolymerizes lignin to vanillin and vanillic acid under mild conditions. The newly reported method overcomes critical barriers in biomass-to-biofuel conversion and lignin valorization, which partially fulfills the Industry's future need. In summary, we believe the conversion of biomass to fuels and chemicals using redox catalysts has many advantages. Still, more fundamental studies on the new catalyst developments should be the near future focuses.
Keywords: Lignocellulosic biomass, redox couple, pretreatment, lignin depolymerization
References 1. Gogoi, Parikshit, Zhe Zhang, ZhishuaiGeng, Wei Liu, WeizeHu, and Yulin Deng*. "Low‐temperature, Low‐Energy, and High‐Efficiency Pretreatment Technology for Large Wood Chips with a Redox Couple Catalyst." ChemSusChem 11, no. 6 (2018): 1121-1131. 2. Zhang, Zhe, ParikshitGogoi*, ZhishuaiGeng, Xinliang Liu, and Xu Du. "Low temperature lignin depolymerization to aromatic compounds with a redox couple catalyst." Fuel 281 (2020): 118799. 3. Du, Xu, Haichuan Zhang, Kevin P. Sullivan, Parikshit Gogoi, and Yulin Deng. "Electrochemical Lignin Conversion." ChemSusChem (2020)DOI: 10.1002/cssc.202001187.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-8
Computational studies on organic semiconductors based on diketopyrrolopyrroles and naphthalenediimides
Dr. Sagar Sharma* Department of Chemistry, School of Fundamental and Applied Sciences, Assam Don Bosco University, Tapesia Gardens, Guwahati, Assam 782402, India *Email: [email protected]
π-conjugated organic semiconductors (OSCs) continue to draw appreciable attention due to their potential optoelectronic device applications such as organic field-effect transistors (OFETs), organic light-emitting diodes (OLEDs),organic photovoltaics (OPVs) , and chemical sensors etc. The present work describes the computational studies on structural, electronic, charge transport properties of organic semiconductors based on common acceptor moieties such as diketopyrrolopyrroles, naphthalene diimides etc. For instance, dketopyrrolo[3,4-c]pyrrole (DPP1), and its regioisomerdiketopyrrolo[3,2-b]pyrrole (DPP2) coupled with various electron donor groups containing fused ring system such as meta-benzodithiophene, ortho-benzodithiophene, carbazole, dithienopyrrole, dithienosilole and dithienothiophenegive model compounds of D-A-D type of architecture (Figure 1). Computational studies based on density functional theory (DFT) calculations show that the DPP2-based compounds have relatively planar structure than the DPP1 counterparts.
In addition they exhibit lower hole reorganization energy (λh) than the corresponding DPP1-based compounds, while the DPP1-based compounds have lower electron reorganization energy (λe) than the corresponding DPP2-based compounds, which is in line with the observed ionization potential (IP) and electron affinity (EA) values. DPP2 based compounds exhibit better intramolecular charge transfer (ICT) properties as compared to their DPP1 counterpart. The weaker electron-hole coherence in case of DPP1-based compounds may lead to easy exciton dissociation at donor/acceptor interface.1
Figure 1: DPP1 and DPP2 based compounds under investigation In case of another class of compounds based on naphthalene tetracarboxylic diimide derivatives., incorporation of electron withdrawing groups such as perfluoroalkyl groups on imide N, leads to significant enhancement of air-stability, π-stacking ability, and charge transport properties of fluoroalkyl side chain engineered n-type naphthalene tetracarboxylic diimide derivatives.
References:
1. Gogoi, G.; Bhattacharya, L.; Rahman, S.; Sarma, N. S.; Sahu, S.; Rajbongshi, B. K.; Sharma, S. Mater. Today Commun., 2020, 25, 101364.
National Seminar on Science for Sustainable Development, SSD-2020
SIL-9
Effect of sea water on the flocculation of iron ore tailings and fines and beneficiation studies: An overview
Jyotirmoy Sarma,*a and Sekh Mahiuddinb
aDepartment of Chemistry, School of basic sciences, Kaziranga University, Jorhat-785006, Assam, India. E- mail: [email protected] bEx-Chief Scientist, Materials Science Division, North-East Institute of Science and Technology, CSIR, Jorhat-785006, Assam, India.
Iron ore fines and slime of low-grade, contain ~ 58% iron and high amount of alumina containing gangue minerals. The surface-active agent used during beneficiation of low-grade iron ore fines and slimeremoves and disperses gangue minerals. To recover water from the suspension and to reduce the volume of the tailing pond, flocculation of suspended gangue minerals is essential. The hard-water flocculates particles in the dispersed phase and generates roughly clear water for reuse.The Al2O3/Fe and Al2O3/SiO2 ratios in the concentrates are appreciably reduced at the isoelectric point of hematite. The recovered water in the presence of humate at different concentrations is found effective in producing stable dispersed phase of iron ore fines and tailings. The beneficiation techniques adopted results in an increase in iron value in the concentrate of iron ore samples.
Keywords: Iron ore tailings, fines, flocculation, surface-active agent, beneficiation.
National Seminar on Science for Sustainable Development, SSD-2020
OP-1
Synthesis of ruthenium complexes and donor properties of N-heterocyclic rings in complexes
1Rinki Moni Kalita, 2Rahul Sarma Baruah, *Chitrani Medhi
1Department of Chemistry, Gauhati University 2Department of Applied Sciences, Gauhati University Email:[email protected] Contact number:6001427221
The ruthenium complexes were synthesised and structures of these complexes are characterised from XRD and spectroscopic techniques. Furthermore computational technique was used to complement the experimental structures.The electron donating ability from the donor sites for the ligand towards Ru can be understood from the reduction of charge density of these atomic sites. Formation of stable complexes is expected from the extent of charge transfer from ligand to Ru. Moreover coordinating ability of donor sites is closely related to the stability of the complexes leading to the variation of redox potential
National Seminar on Science for Sustainable Development, SSD-2020
OP-2
ELECTRONIC PROPERTIES OF RUTHENIUM COMPLEXES HAVING VINYL IMIDAZOLE LIGAND
1Rahul Kumar Sarma Baruah* and 2Rinki Moni Kalita
1Department of Applied Sciences, Gauhati University, Guwahati, Assam, India 2Department of Chemistry, Gauhati University, Guwahati, Assam, India Presenting author : Rahul Kumar Sarma Baruah ( Email : [email protected]) Corresponding author: Rinki Moni kalita( Email : rinkymoni16dec@gmail)
In this work, the ligand vinyl imidazole (VIm) complexes of Ruthenium(Ru) were taken and one electron redox potentials were analysed. The structures and the influence of ligand in these ruthenium complexes on the one electron transfer mechanism were investigated. Ligand charge transfer towards the Ru metal has been found prominent in these Ru-ligand complexes forming a strong coordinated bond.The one electron transfer processes of these complexes depend on the number of VIm ligands present in these complexes.
National Seminar on Science for Sustainable Development, SSD-2020
OP-3
DYES INTERCALATED ON MESOPOROUS PARTICLES ASSENSORS Sarojmoni Kalita and Diganta Kumar Das*
Department of Chemistry, Gauhati University-781014
Design and development of novel sensitive and cost-effective electrochemical and fluorescent sensorsbased on various classes of nanomaterials such as mesoporous silica particles fabricated by different methods for the detection of biomolecules, heavy metal ions and environmental pollutants are reviewed as being highly sensitive, cost effective and repeatable [1]. Dopamine(DA) plays an important role in several conditions such as Parkinson’s disease, schizophrenia, etc. and its detection is often interfered by ascorbic acid as its biological concentration is higher than that of DA [2]. Also the heavy metal ions, such asCu (II) is non‐biodegradable pollutants and can accumulate in environment and in living tissues [3]. In this work, we have successfully intercalated dyes Rosaniline hydrochloride and Sudan Black into MCM- 48 (L1 and L2). The encapsulation has been proved by various characterisation techniques. L1has successfully detected DA in its aqueous solution without the interference of other biomolecules in aqueous solutionas well in biological system. L2can be used as both as paper sensor and fluorescent nanaosensor for detection of Cu(II) in aqueous solution.
National Seminar on Science for Sustainable Development, SSD-2020
OP-4
N-Heterocyclic Carbene Magnesium Chemistry: Synthesis and Catalysis Dr. Ashim Baishya and Dr SharanappaNembenna
School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar Email: [email protected] In modern technological processes nearly 85-90% of all chemicals require a catalyst for their production. In this context, late transition metal based catalysts(for example Ir, Pd, Ru, Rh etc) are most demanding and very frequently used because of their exceptional ability to activate relatively inert non-polar chemical bonds such as H-H or C-H linkages. However, application of such systems is likely to become more and more difficult due to their lack of sustainable availability, together with the high cost and toxicity of these metals. Therefore, replacement of precious transition metals with inexpensive, abundant and less toxic (in most cases) main group element analogues are at the cutting edge of modern research. [1] In this presentation I focus on the synthetic strategies toorgano-magnesiumcomplexes and their catalytic applications (Scheme 1).Notably, IMes carbene stabilized organo-magnesium halide/amide and cyclometalated complexesare explained. The six membered magnesiummetallacycle represents the first example where the magnesium mediatesthe C(sp3)-H bond activation and undergoes cyclization. [2]Furthermore, theorgano-magnesium amide catalyzedcross de-hydrogenative coupling of amines withsilanesiselaborated. [3]
Scheme 1.Synthesis of IMesmagnesium complexes and catalyzed cross coupling of amines with silanes;
References: [1] Power, P. P. Nature2010, 463, 171-177; [3] Magnesium mediated C(sp3)-H activation and cyclization of IMes carbene, BaishyaA., Barman M. Kr., BiswalH. S. and NembennaS. *manuscript under preparation; [2] BaishyaA., PeddaraoT. and NembennaS.*Dalton Trans.2017, 46, 5880.
National Seminar on Science for Sustainable Development, SSD-2020
OP-5
Analysis of dietary fibre of some indigenous vegetables of Assam
Pankaj Saikia
Department of Chemistry, Tinsukia College, Tinsukia-786125 Email: [email protected]
Dietary fibre (DF) is defined as the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine [1]. Dietary fibre (DF) plays a significant role in human health. Scientific studies have established that DF acts as protective agent against cardiovascular diseases, diverticular diseases, constipation, irritable colon, colon cancer and diabetes [2]. Some indigenous vegetables were analysed for soluble dietary fibre (SDF), insoluble dietary fibre (IDF) and total dietary fibre (TDF) contents. TDF content of the vegetables ranged from 3.12 to 4.82 g/100 g whereas IDF and SDF ranged from 2.62 to 4.21 g/100 g and 0.41 to 0.65 g/100 g respectively. The detailed findings will be presented and discussed.
Key words: Dietary fibre, Insoluble dietary fibre, Soluble dietary fibre
References:
[1]. American Association of Cereal Chemist (2001). The definition of dietary fibre. Report of the Dietary Fibre Definition Committee to the Board of Directors of the AACC 1, 10.
[2]. Yapo B. M. &Koffi K. L. (2008). Journal of Agricultural and Food Chemistry, 56, 5880-5883.
National Seminar on Science for Sustainable Development, SSD-2020
OP-6
Ultra-Weak Metal-Metal Bonding: Does a Beryllium-Beryllium Triple Bond Exist?
Shahnaz S. Rohman, ChayanikaKashyap, Sabnam S. Ullah, Ankur K. Guha*, Lakhya J. Mazumder and Pankaz. K. Sharma Department of Chemistry, Cotton University, Assam, India-781001 *E-mail:[email protected] Metal-metal multiple bonding is a common phenomenon in d-block metals. However, such multiple bonds in s-block metals are rare. Among the s-block metals, beryllium possesses the highest electronegativity as well as ionization energy and hence, chemically bonded Be-Be interaction is the most studied s-block metal-metal interactions.[1,2]As for instance,ultraweak and ultrashort Be-Be distances with little or no bond has frequently been observed.[3,4,5] The weak bond [6] dissociation energy (BDEBe-Be) of 0.1 eV in Be2 dimer is responsible for such little or no interaction. Many theoretical strategies were proposed for strengthening the Be-Be interaction. Among them the most noticeable proposal was put forward by Liu et. al[7]. In their work, they proposed a unique way of strengthening the Be-Be interaction by concerted electron donation from the vertical plane of the Be-Be midpoint to achieve true double π bonds.The calculated Wiberg Bond Index (WBI) value of the Be-Be bond in Li4Be2 molecule was found to be 1.963. Different bonding analyses showed the existence of only two π bonds in Li4Be2 without any σ bond. This remarkable proposalposed a question into our mind: Does a true Be-Be triple bond exist? Herein, with the aid of high level abinitiocalculations we have shown that, indeed, a true triple bond exists between the Be atoms in Li6Be2molecule.We have theoretically predicted a novel species featuring the first Be-Be triple bond in Li6Be2 molecule. The molecule has been found to be thermodynamically stable. The presence of the triple bond has been confirmed by adaptive natural density partitioning (AdNDP), electron localization function (ELF) and atoms in molecules (AIM) analyses. Moreover, the mechanical strength of the Be-Be triple bond has been analyzed by using compliance matrix which suggests its ultra-weak nature.[8]
References: [1] J. M. Merritt, V. E. Bondybey, M. C. Heaven, Science2009, 324,1548-1551. [2] K. Patkowski, V. Špirko, K. Szalewicz, Science 2009, 326, 1382-1384. [3] C. Yuan, X. F. Zhao, Y. B. Wu, X. Wang,.Angew. Chem. Int. Ed. 2016, 55, 15651-15655. [4] Q. Zhang, W. L. Li, L. Zhao, M. Chen, M. Zhou, J. Li, G.Frenking, Chem. Eur. J. 2017, 23, 2035-2039. [5] X. Liu, M. Zhang, S. Yu, Y. Geng, X, Zhang, Y. Ding, Z. Su, Phys. Chem. Chem. Phys, 2018, 20, 23898-23902. [6] A. V. Mitin, Int. J. Quantum Chem. 2011, 111, 2560-2567. [7] X. Liu, M. Zhang, S. Yu, Y. Geng, X, Zhang, Y. Ding, Z. Su, Phys. Chem. Chem. Phys, 2018, 20, 23898-23902. [8] S. S. Rohman, C. Kashyap, S. S. Ullah, A. K. Guha, L. J. Mazumder, P. K. Sharma,ChemPhysChem, 2019, 20, 516-518.
National Seminar on Science for Sustainable Development, SSD-2020
OP-7
Base Promoted Synthesis of Quinoline-4(1H)-thiones and itsThiocarbonylDirected Regiospecific C-H/S-H Annulation with Alkynes
Anju Modi, PrasenjitSau, Nikita Chakraborty, and Bhisma K. Patel*
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India E-mail: [email protected]
A metal-free cascade synthesis of quinolin-4(1H)-thiones has been accomplished by reacting o-alkynylanilines with aroyl/acyl isothiocyanates in the presence of a base. The reaction proceeds via the in situ generation of o-alkynylthiourea, which undergoes 6-exo-dig S-cyclization followed by rearrangement resulting into simultaneous formation of C-C, C-N and C-S bonds in 100% atom economy. The synthesized molecule was utilized as directing substrates for annulation reaction with internal/external alkynes in the presence of Ru(II) catalyst, leading to the synthesis of thiopyrano[2,3,4-de]quinolines. This is the first example of any C-H/S-H annulation directed via a C=S group. Here, preferential annulation takes place at the sterically hindered position even in the presence of three other competing sites viz. two C-H/N-H and one C-H/O-H.The reaction proceeds via ruthenium-catalyzed oxidative annulation followed by hydrolytic cleavage of an amidic bond(- COPh group) leading to the synthesis of the annulated product.
References- 1. A. Modi, P. Sau, N. Chakraborty. B. K. Patel, Adv. Synth. Catal. 2019, 361, 1–9 2. A. Banerjee, S. K. Santra, P. R. Mohanta, B. K. Patel, Org. Lett.2015, 17, 5678 3. A. Modi, P. Sau, B. K. Patel, Org. Lett.2017, 19, 6128.
National Seminar on Science for Sustainable Development, SSD-2020
OP-8
Trace Element Contamination and Human Health Risk Assessment in Drinking Water of a Small Town of Lower Assam
Basanta Kumar Das* and Himojjal Medhi
Department of Chemistry, Kokrajhar Govt. College, Kokrajhar – 783370 E-mail: [email protected]
The degradation of environment and some illegal human intervention in the natural system has increased the concern for the betterment of healthy living. In the name of so called development some activities of people are creating imbalance in the natural system. Due to such activities the first and most affected part of nature is the aquatic system. It is known that balanced intake of some trace metals are important for human health. But their excessive amount or prolong consumption is harmful. Contamination of trace element has become major source of global environmental pollution. The present paper mainly shows the trace elements (As, Cr, Fe, Ni and Pb) concentrations in the drinking water of Basugaon town and their possible effect on the health of the inhabitants. Some other physicochemical parameters are also analyzed. The statistical analysis of the data shows positive correlation between some parameters. For this purpose 10 different sampling stations were selected from different parts of the town. The water samples are then analyzed by standard methods for temperature, pH, electrical conductivity; total dissolved solid (TDS), hardness, calcium, magnesium, chloride, sulfate, nitrate, fluoride, arsenic, iron, nickel, chromium and lead. Sampling was done in post monsoon of 2019. The average concentration of chromium, iron, nickel and lead were found more than the prescribed limit of WHO in most of the sources. The study shows that the water quality of the town is not satisfactory with respect to some parameters like Fe, Cr, Ni and Pb. However, most of the water samples did not have high concentrations of toxic contaminants, like fluoride and arsenic. As the whole town is industrially underdeveloped, chemical contamination from industrial sources is insignificant, yet the water cannot be categorized as pollution free.
Key Words: Trace element, Water quality, Human health, Contamination, Correlation.
National Seminar on Science for Sustainable Development, SSD-2020
OP-9
Evidence of protonation induced intra-molecular metal-to-metal charge transfer
in a highly symmetric cyanido bridged {Fe2Ni2} molecular square
PrashuryaPritamMudoi, BipulSarma and NayanmoniGogoi* Department of Chemical Sciences Tezpur University, Napaam, Sonitpur, Assam 784028 E-mail: [email protected], [email protected] Discovery of photo-chemically induced reversible magnetic switching in a Co/Fe Prussian Blue,
K0.2Co1.4[Fe(CN)6]·6.9H2O,in 1996, by Hashimoto and co-workers triggered a perpetual surge of interest in cyanido bridged magnetic materials.1In view of their immense potential in modern technological applications, quest for designer, Prussian Blue Analogue (PBA) materials with improved characteristics have intensified during the last few years. The discovery fevered an outburst of activities to design discrete external stimuli responsive PBAs. Indeed, stimuli responsive intra-molecular metal-to-metal charge transfer (MMCT)accompanied by concomitant electronic structure switching is also observed in several cyanido-bridged molecular PBAs.2,3The possibility to induce intra-molecular metal-to-metal charge transfer in a cyanido bridged tetranuclear square shaped {Fe2Ni2} complex by employing protonation as an external stimulant was explored (Fig.1). Cyanido bridged square shaped tetranuclear complex [{Ni(TPA)(μ2-NC)2Fe(bbp)(CN)}2] (1) [TPA = tris(3,5-dimethylpyrazol-1-ylmethyl)amine and H2bbp= bis(2-benzimidazolyl)pyridine] was synthesized and characterized. Low temperature magnetic measurements revealed that complex 1 has dominant ferromagnetic interactions between low-spin FeIII (S = 1/2) and high-spin NiII (S = 1) ions. UV-visible spectrophotometric measurements and electrochemical studies established that reversible intra-molecular metal-to-metal electron transfer can be triggered in 1 upon addition of either acid or base.
Fig.1:Graphical representation of protonation induced intra-molecular MMCT in {Fe2Ni2} molecular square. References 1. O. Sato, T. Iyoda, A. Fujishima and K. Hashimoto, Science, 1996, 272, 704-705. 2. C. P. Berlinguette, A. D. Andrasi, A. Sieber, J. R. G. Mascarós, H.-U. Güdel, C. Achim and K. R. Dunbar, J. Am. Chem. Soc., 2004, 126, 6222-6223. 3. D. Aguilà, Y. Prado, E. S. Koumousi, C. Mathonière and R. Clérac, Chem. Soc. Rev., 2016, 45, 203-224.
National Seminar on Science for Sustainable Development, SSD-2020
OP-10
A facile green synthetic strategy forpyrazolo[1,5-a]pyrimidineswith potent anti- bacterialproperties
Susma Das1, Jayanti Dutta2, Jai Narayan Vishwakarma1,* 1. Organic Research Laboratory, Department of Chemical Science, Assam Don Bosco University, Tapesia Gardens, Kamarkuchi, Sonapur – 782 402 Assam, India 2. ICAR Research complex for NEH region, Umiam (Borapani), Meghalaya-793103, India Corresponding author: [email protected]
Pyrazolo[1,5-a]pyrimidine is a very interesting and important heterocyclic moiety due to its resemblance with purine analogues[1]. Numerous studies have shown that this heterocyclic system has been blessed with many important biological properties, some of which are anti-fungal, anti-microbial, anti- bacterial, anti-insomnia, anti-cancerous, anti- neuropsychiatric inhibiting properties [2-4]. There are many commercial drugs which have pyrazolo[1,5-a]pyrimidine as the active core [5]. In continuation with our motto [1, 2, 5-6] of designing, synthesizing and exploring their bioactivities, we have developed synthetic strategiesfor the synthesis of novel pyrazolo[1,5-a]pyrimidines 3(a-o)by reacting 3- aminppyrazole 1 with various enaminones 2(a-o). Our strategy is eco-friendly as we have used here the non- conventional ultrasonic irradiation to obtain the desired products. We have used a mild acidic condition, which contributed to our environment friendly concepts. This method has robustly increased the yield decreasing the reaction time from few hours in traditional set-up to few minutes, with product found to be practically pure and in higher yields.The structures of these 15 compounds were established with the help of spectral and analytical data (1H NMR, 13C NMR, IR and mass spectrometry). One of these compounds is chosen as a model and its single-crystal X-ray crystallography was studied, which has further confirmed its structure. All the compounds were screened for their anti-bacterial properties via well-diffusion method against two gram positive (Escherchia coli andKlebsiella pneumonia) and two gram negative bacteria (Listeria monocytogenes and Staphylococcus aureus). Five of these compounds were found to exhibit quite encouraging anti-bacterial activities against E. coli for 7-8 hours, hence exhibiting bacteriostatic activities. But they did not give any response against the other bacteria.
Scheme 1: Schematic representation of synthesis of various bio-active pyrazolo[1,5-a]pyrimidine derivatives via a green synthetic protocol.
References
1. U. Kalita; S. Kaping; J. Nellant; P. Helissey; J. N. Vishwakarma; Heteroletters 2014, 4(1), 137-145, 68. 2. S. Kaping; I. Boiss; L. I. Singha; P. Helissey; J. N. Vishwakarma; Mol Divers 2015, 20(2), 379-390. 3. S. Mikami; M. Kawasaki; S. Ikeda; N. Negoro; S. Nakamura; I. Nomura; T. Ashizawa; H. Kokubo; I. D. Hoffman; H. Zou; H. Oki; N. Uchiyama; Y. Hiura; M. Miyamoto; Y. Itou; M. Nakashima; H. Iwashita; T. Taniguchi; Chem. Pharm. Bull. 2017, 65, 1058-1077. 4. A.S. Hassan; G. O. Moustafa; H. M. Awad; Synth Commun. 2017, 47(21), 1963-1972. 5. S. Kaping; U. Kalita; M. Sunn; L. I. Singh; J. N. Vishwakarma; MonatshChem 2016, 147(7), 1257- 1276. 6. S. Kaping; M. Sunn; L. I. Singha; J. N. Vishwakarma; Eur J Chem. 2020, 11(1), 68-79.
National Seminar on Science for Sustainable Development, SSD-2020
OP-11
Naked eye detection of Nitrophenol vapours via band gap engineering in Perylene HOFs
Abhishek Borborah and Dr. Sanjeev Pran Mahanta.
Department of Chemical Sciences, Tezpur University, Napaam, Tezpur-784028, India. e-mail id: [email protected]
Nitrophenols are important constituent in the production of pigments, rubber chemicals, lumber preservatives, photographic chemicals, and fungicide agents. It is highly toxic and has severe impacts on living organisms as well as the environment. Hence, its detection in low concentrations particularly through naked eye is sought after. This work elucidates the development of a new Perylene hydrogen bonded framework (PHOF) capable of rapid and cost-effective detection ofnitrophenol vapours in low concentration via band-gap engineering. Compared to other organic semiconductors perylene compounds are advantageous regarding the ease of band gap modulation that can be achieved by functionalization at their imide position. Herein, PHOF is synthesised by self-assembly of perylenetetracarboxylate and guanidium via hydrogen bonding reinforced with electrostatic interaction. Our approach bypasses organic synthetic routes to modify the band structures of the H-bonded organic framework. This principle helps to fine tune the optoelectronic properties of perylene based compounds and be applied for colorimetric detection of nitrophenols without the requirement of solvent systems.
Figure: Colour change of PHOF before exposure (left) and after exposure (right) to nitrophenol vapour.
References (1) Ascherl, L.; Evans, E. W.; Gorman, J.;Orsborne, S.; Bessinger, D.; Bein, T.; Friend, R. H.; Auras, F. J. Am. Chem. Soc., 2019, 141, 15693-15699. (2) Würthner, F.; Saha-Möller, C. R.; Fimmel, B.; Ogi, S.; Leowanawat, P.; Schmidt, D. Chem. Rev., 2016, 116, 962−1052. (3) Geng, T.; Chen, G.; Zhang, C.; Ma, L.; Zhang, W.; Xia, H.Journal of Macromolecular Science, Part A,2019, 56, 1004-1011.
National Seminar on Science for Sustainable Development, SSD-2020
OP-12
Remaking the way from waste: a sustainable strategyof chitosan- polybenzoxazine-sulfur composite beads for heavy metal removal from waterand crude oil spill remediation
Saad Zafar#, VigneshNayak#, Nisha Yadav and BimleshLochab*
Materials Chemistry Laboratory, Department of Chemistry, School of Natural Sciences, Shiv Nadar University, Gautam Buddha Nagar, Uttar Pradesh 201314, India. # Equal Contribution *Corresponding Author: [email protected]
For decades, the contamination of water has been a central environmental concern throughout the world. Oil pollution and heavy metal contamination are serious concerns for the environment. Oil spills threaten ground water, drinking water, and food staples such as fish and other aquatic organisms. On the other hand, mercury is extremely toxic to living organisms if found in any form. Even low doses can cause serious disorders of the kidney, liver, brain and central nervous system of humans and animals. Because of these ongoing challenges, exploration of cost-effective technologies and environmentally friendly sorbents are in high demand to mitigate these issues. Herein, we have reported waste derived composite beads synthesized from chitosan- polybenzoxazine-sulfur composite. The beads were developed via simple coagulation method in basic medium. The beads showed good antiwetting property towards water owing to the presence of sulfur and benzoxazine. Due to this hygroscopic nature, these beads were able to adsorb oil efficiently from the water surface.In addition, presence of sulfur proved to be beneficial for Hg adsorption from water. SEM analysis demonstrated porous inter-connecting network of the beads and uniform distribution of benzoxazine-sulfur copolymer in beads. The beads showed good compressive strength and structural integrity on compression as indicated by compressive strength analysis. The beads showed excellent reusability competence performing upto5 consecutive oil sorption cycles (without squeezing technique) and 3 cycles (with squeezing technique) with the morphology of the beads nearly unchanged.Along with this these beads adsorbed mercury from the water body upto 99% which was confirmed by ICP-OES and the interaction of mercury with polymeric beads by XPS analysis was studied. This study isworking towards greener chemistry and successfully using the concept of waste valorization.
National Seminar on Science for Sustainable Development, SSD-2020
OP-13
Highly stable nanostructured Co3O4-CeO2/C hybrid as an efficient electrocatalyst for oxygen reduction reaction
Chiranjita Goswami and Pankaj Bharali*
Department of Chemical Sciences Tezpur University, Napaam, Sonitpur, Assam 784028 *E-mail:[email protected], [email protected] Oxygen reduction reaction (ORR) is the most important reaction that occurs in the cathode of fuel cells. Its sluggish kinetics stimulated the researchers towards the development of inexpensive as well as efficient alternatives to the precious Pt-based catalysts. A non-precious metal-oxide hybrid electrocatalyst (EC) was developed, which comprised of nanostructured Co3O4 and CeO2 anchored on a carbon support (Co3O4-CeO2/C hybrid) with adequate oxygen vacancies and strong oxide/oxide and oxide/carbon hetero-interfaces. The resultant Co3O4-CeO2/C hybrid acts as a high- performance EC for ORRwith high stability and durability in alkaline medium. Co3O4-CeO2/C hybrid can afford an Eonset and E1/2 of ‒0.12 and ‒0.28 V (vs. Ag/AgCl), respectively, which is very close to the benchmark Pt/C catalyst for ORR.The resultant hybrid also shows the highest limiting -1 current density as evident from Fig. 1. The Tafel slope of Co3O4-CeO2/C hybrid (69mV decade ) for ORR also indicates similar reaction kinetics like that of Pt/C catalyst (68 mV decade-1). Thus, the current work represents a promising route to replace noble metals and to develop low-cost cathode material for alternative energy devices.
Fig. 1. Comparison of ORR activity of the catalysts in terms of current density in 0.1 M KOH electrolyteat 1600 rpm.
References:
3. Goswami, C.; Saikia, H.; Tada, K.; Tanaka, S.; Sudarsanam, P.; Bhargava, S. K.; Bharali, P. ACS Appl. Energy Mater.2020, DOI:10.1021/acsaem.0c0162. 4. Borah, B. J.; Yamada, Y.; Bharali, P. ACS Appl. Energy Mater.2020, 3, 3488–3496. 5. Goswami, C.; Hazarika, K. K.; Bharali, P. Mater. Sci. Energy Technol.2018, 1, 117–128. 6. Hazarika, K. K.; Goswami, C.; Saikia, H.; Borah, B. J.; Bharali, P. Mol. Catal.2018, 451, 153–160.
National Seminar on Science for Sustainable Development, SSD-2020
OP-14
Electrocatalytic oxidation of water by a copper complex containing Histidine derived ligand
Swati Basak, Diganta Choudhury* Department of Chemistry, B. Borooah College, Guwahati, Assam-781007, India Email: [email protected]
Catalytic splitting of water by oxygen evolving complex (OEC) to yield O2, proton and electron in natural photosynthesis is a vital reaction for the harvesting of solar light energy in the form of reduced food stuff. Scientist around the world is trying to mimic the activity of OEC through synthetic compounds out of which transition metal complexes finds high importance. 1–3 A large numbers of metal complexes have been reported with the ability of electrocatalytic oxidation of water in neutral, acidic and basic media. In view of cost effectiveness and robustness, copper based complexes have emerged as potential water oxidation catalysts. In the present work, we have described the synthesis and electrocatalytic activity of a copper (II) complex having Histidine derived ligand which shows high catalytic activity at neutral pH.
References: 1. Barnett, S. M.; Goldberg, K. I.; Mayer, J. M. Nat. Chem. 2012, 4, 498. 2. Zhang, M. T.; Chen, Z.; Kang, P.; Meyer, T. J. J. Am. Chem. Soc. 2013, 135, 2048. 3. Coggins, M. K.; Zhang, M. T.; Vannucci, A. K.; Dares, C. J.; Meyer, T. J. J. Am. Chem. Soc. 2014, 136, 5531.
National Seminar on Science for Sustainable Development, SSD-2020
OP-15
Critiquing Sustainability: Migratory Pathogens and Conflict of Interests in Context
Manabendra Sarma
Assistant professor Department of English B.Borooah College Email- [email protected]
Apart from other things the present Pandemic has given us the opportunity to ponder over the vulnerability of human sustainable practices. Scholars and philosophers in Europe and America have been involved in insightful debates regarding the tenacity of the military approach to harness the spread of Covid-19. What most of the countries have used is a combination of military and medical approach to confine the disease. Such an approach have been criticised for its lack of humane face. Despite the relentless efforts of global political leaders, administrators, medical practioner and researchers there seems to be no respite from the malady. The lock horning of global economic powers in post Corona world will bring about unprecedented structural changes in almost all aspects of human concern. The shifting focus from public health to political and economic concerns appears to be a diverting strategy employed by global powers to confuse the already confused humanity. The conflict of humanitarian and commercial interests is however, not a new one. This paper draws from the epidemic history of Europe two important episodes – the plague during the seventeenth century England and the Hamburg Cholera incident to justify the argument that we have been playing the same old politics to counter the new pathogens. Parallel to the unprecedented developments in communication technology human migration has also seen an upsurge in recent times. Increased human mobility has induced migration of pathogens across national borders. Entry of foreign pathogens into new geographical territories has also increased the vulnerability of human life. Is the present state of affairs threatening the way we conceptualise ‘sustainability’? Based on this question this paper is an attempt to provide a critique of the received model of sustainability in the context of the current pandemic.
Key Words – Millitary approach, Plague, Hamburg Cholera incident, migration of pathogens, sustainability.
National Seminar on Science for Sustainable Development, SSD-2020
OP-16
Trends of Higher Education in a Sustainable Future
Dr. Satyabrata Baruah,1 Ms. Sarmistha Choudhury2 1. Assistant Professor, Department of Education, B. Borooah College, Guwahati, Assam 2. Assistant Professor, Department of Education, USTM, Meghalaya
Quality education is one of the pillars for Sustainable Development. For sustainability education should aim to ensure inclusive and equitable education and promote lifelong learning opportunities for all. Education is also one of the calculable indicators of the Human Development Index (HDI) which is a fundamental dimension of sustainable development assessment. It is clear that education is the key to the future of the quality of human life and the sustainability of the world. Generally, education is being transformed in both formal and informal learning contexts by new digital technologies. New technologies in education are changing our ideas, conceptions and even broadening the objectives of education. Each of these trends carries risks and dangers as well as new possibilities in the field of education. This paper is an attempt to provide a brief outline about 1) our educational aims and objectives 2) the processes of learning 3) the processes of teaching and 4) educational governance and policy in the context of the scenario of higher education in Assam.
Key words: Higher Education, Sustainable Development
National Seminar on Science for Sustainable Development, SSD-2020
OP-17
Hyperbranched Polymer-Supported Graphitic Carbon Nitride Nanodots for Photocatalytic Oxidation and Reduction Reactions
Rajarshi Bayan and Niranjan Karak*
Advanced Polymer & Nanomaterials Laboratory Department of Chemical Sciences, Tezpur University Sonitpur, Assam, India Email: [email protected], [email protected]
Safe, sustainable and efficient methodologies are much desired trends in catalysis recently from green chemistry point of view. The current work reports the development of oxygeneous graphitic carbon nitride nanodots-loaded hyperbranched polyurethane as a heterogeneous photocatalyst. Experimental studies reveal that the carbon nitride nanodots possess remarkable optical properties. The nanodots display excitation wavelength-dependent photoluminescence emission behaviour, along with an optical band gap of 2.93 eV, which facilitates effective photo- harvesting ability. Inclusion of the nanodots within a eco-friendly polymer ensures their stability in catalytic activity and also provides a heterogeneous character for facile catalyst recovery and reuse. The photocatalyst exhibit optimal performance in driving oxidative and reductive organic transformations under solar light. The current work aims to promote a robust, efficient and sustainable metal-free heterogeneous photocatalytic system for simple organic transformations.
References:
1. Bayan, R. and Karak, N. Bio-based hyperbranched polymer-supported oxygeneous graphitic- carbon nitride dot as heterogeneous metal-free solar light photocatalyst for oxidation and reduction reactions. Applied Surface Science, 2020, 514, 145909. 2. Bayan, R. and Karak, N. Photoluminescent oxygeneous-graphitic carbon nitride nanodot- incorporated bioderived hyperbranched polyurethane nanocomposite with anticounterfeiting attribute. ACS Omega, 2019, 4 (5), 9219-9227.
National Seminar on Science for Sustainable Development, SSD-2020
OP-18
Why Scientific Education matters to Health and Wellbeing: A Study on Indian Context
Dr. Chandan Sharma
Assistant Professor, Department of Economics, Morigaon College [email protected]
The traditional medical model defines health as a state of absence of disease or illness but the World Health Organization (WHO) links wellbeing to define health. According to the WHO health is a ‘state of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity’. Health is both social and personal resources. A healthy person not only improves his ability to fulfill requirements but also contributes the society as productive resource. Good health depends on factors like access to healthcare, genetics, environment, relationship, income and education level. Among these factors there is significant relationship between health and education, particularly science education. This relationship is two ways—education can create opportunities for better health and similarly, poor health can put education at risk (reverse causality). It is established fact that people with higher education is likely to get good jobs and ensured income. The job automatically provides health promoting benefits like health insurance, earned leave, retirement security etc. At the same time, the higher income enable them to purchase healthy diet, pay for health services, spend for leisure and recreation, pay for safe transportation etc. Conversely, less education means job insecurity, forced to work high risk jobs with few medical benefits. Their lower income makes them unable to meet adequate healthcare services, balanced diet, proper housing which adversely affect their health. In India the govt. fails to spend adequate amount of money in both education and healthcare. Low level of educational attainment forces the people to engage in informal sector which is as high as 92 percent. These informal workers are not entitled to health insurance or healthcare services in the work place. Besides their income is insecure and limited which make them unable to avail costly private sector health services. Since, govt. sector health services are neither updated in many cases nor adequate in comparison the population size, most of the people deprive from medical services. They rather prefer to go for local medicine men in case of facing health trouble or take refuse in the feet of religious Gurus. As a result many superstitions and ill practices still wide spread among the people. All these hinder the wellbeing of the people. This paper tries to analyze the govt. spending on education and health sector in India and also study the role played by education in spreading healthcare services and raising wellbeing of the people. It is found that govt. spending is far below from the desired level in both the sector. The lower social investment is responsible for informalization of the economy and less wellbeing of the people including prevailing superstitions.
Key Words: Education, Science, Health, Wellbeing, Income
National Seminar on Science for Sustainable Development, SSD-2020
OP-19
Ferrocene Appended Novel Iron(III)-Esculetin Complex as a Dual-Pathway Phototheranostic Agent Tukki Sarkar, Arnab Bhattacharyya, Samya Banerjee, and Akhtar Hussain Department of Chemistry, Handique Girls’ College, Panbazar, Guwahati 781001, Assam E-mail: [email protected]
There is a strong ongoing interest in redox-active transistion metal complexes that can trigger photo-induced apoptosis of cancer cells for their potential applications as next-generation photochemotherapeutics. For example, current interst in iron(III) complexes as photochemotherapeutic drugs stems largely due to the clinical success of iron-bleomycin as natural antitumor antibiotic and the faoarbale redox and photophysical properties of the complexes. We have developed two novel mixed-ligand iron(III) complexes with a naturally occurring photoactive 6,7- dihydroxycoumarin (esculetin) ligand and an appended ferrocenyl moiety and study them as red light PDT agents. We have synthesized and characterized two new iron(III) complexes of general formula [Fe(FcCH2-dpa)(L)Cl] (1, 2), where FcCH2-dpa is a ferrocene appended tridentate dipicolylamine base, namely, ferrocenyl-N,N-bis((pyridin-2-yl)methyl)methanamine, and L is a bidentate catecholate ligand derived from 1,2-dihydroxybenzene (1) and 6,7- dihydroxycoumarin (2). The single- crystal X-ray structure of complex 1 shows distorted octahedral geometry around the iron(III) center. The 1:1 electrolytic complexes are stable five electron paramagnetic species and display a broad LMCT absorption band around 750 nm (red light). Complex 2 shows green emission around 520 nm when excited at 395 nm. Complex 2 shows striking cytotoxicity in red light against HeLa, MCF-7 and HaCaT cancer cells (IC50 ~5 µM) while being non-toxic in the dark
(IC50 >50 µM). The corresponding catecholate complex 1 was non-toxic under identical conditions. Complex 2 was non- toxic to MCF-10A normal cells thereby demonstrating its selectivity towards cancer cells. The mode of cell death was found to be apoptotic in nature as revealed from the PI staining assay. The apoptotic cell death is attributed to the photo- induced generation of ROS as ascertained from the DCFDA assay. Complex 2 generates singlet oxygen (type-2 pathway) in visible light as revealed from the absorption spectral study using ABDA as singlet oxygen probe. In red light, complex 2 leads to the formation of superoxide and peroxide radicals as ROS by a photoredox mechanism (type-1 pathway) involving the iron(III) center and the photoactive esculetin ligand. Confocal imaging of HeLa cells revealed primarily mitochondrial localization of complex 2. Thus, complex 2 has remarkable properties as a dual-pathway (both type 1 and type 2) PDT agent and as an imaging agent. It is a potential phototheranostic (phototherapy and imaging) agent.
Figure: (a) ORTEP view of complex 1 at 50% thermal probability and (b) DFT optimized structure of complex 2. References (1) Monro, S.; Colón, K. L.; Yin, H.; Roque, J. III; Konda, P.; Gujar, S.; Thummel, R. P.; Lilge, L.; Cameron, C. G; McFarland, S.A. Chem. Rev. 2019, 119, 797. (2) Sarkar, T.; Bhattacharyya, A.; Banerjee, S.; Hussain, A. Chem. Commun. 2020, 56, 7981. (3) Sarkar, T.; Banerjee, S.; Mukherjee, S.; Hussain, A. Dalton Trans. 2016, 45, 6424. (4) Sarkar, T.; Butcher, R. J.; Banerjee, S.; Mukherjee, S.; Hussain, A. Inorg. Chim. Acta 2016, 439, 8. (5) Sarkar, T.; Banerjee, S.; Hussain, A. RSC Adv. 2015, 5, 29276. (6) Sarkar, T.; Banerjee, S.; Hussain, A. RSC Adv. 2015, 5, 16641.
National Seminar on Science for Sustainable Development, SSD-2020
OP-20
2,2′-bibenzimidazole based Ruthenium(II) Precatalysts for Oxidation of Alkenes: Breaking the Barrier with Cooperativity Manali Dutta, Kusum Kumar Bania and Sanjay Pratihar* Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India. Email: [email protected]
Herein, in this chapter, we discuss the utilisation of 2,2′-bibenzimidazole (BiBzImH2) as bidentate ligand to connect two electronically different pairs of ruthenium complex fragments such as
Ru(BPy)2Cl2 and [Ru(para-cymene)Cl2]2 to generate a cooperative bimetallic Ru(II) precatalyst for selective oxidative C-C multiple bond cleavage reaction. This bimetallic complex was found to be more active compared to its monometallic counterparts because of the following reasons: (i) the variable coordination (two imino N→Ru & two amido N–Ru) of BiBzImH2 with two electronically different Ru(II) center is expected to enhance the electron transport ability with notable electronic coupling, (ii) the acceptor property of Ru(BPy)2Cl2 moiety will enhance the oxidative stress at catalytically active (para-cymene)Ru centre for faster release of para-cymene for the generation of high valent bimetallic Ru(BPy)2(BiBzIM)RuO2, (iii) enhanced electron transport ability of the system through BiBzIM is anticipated to provide kinetic stability to Ru(BPy)2(BiBzIM)RuO2 and also expected to facilitate its reversible interconversion to other active species in presence or absence of substrate, (iv) finally, cooperative effect is expected to enhance both selectivity and reactivity of the bimetallic complex for oxidation of alkenes to aldehydes/ketones as compared to its monometallic counterparts. In the present study, we report the synthesis and characterization of bisbenzimidazole ligand and its corresponding bimetallic and monometallic Ruthenium complexes, in which [Ru(p-cymene)Cl]2 was used as the precursor complex. The synthesised complexes were characterized using various analytical techniques like NMR, UV-visible, ESI-MS and Cyclic Voltametry. The catalytic activity of the complex was studied in the oxidation of olefins to aldehydes or ketones. The products were isolated in good to high yields. The kinetics of the reaction with respect to different reaction parameters were investigated through GC-analysis and finally the mechanistic study was done through spectroscopic, kinetic and other controlled experiments.
Styrene NaIO4
Aldehyde
Figure. Ruthenium precatalyst mediated oxidation of styrenes to aldehydes.
References: 1. Ishizuka, T., Kotani, H., and Kojima, T. Characteristics and reactivity of ruthenium–oxo complexes. Dalton Transaction, 2016, 45(42):16727-16750. 2. Yang, D., and Zhang, C. Ruthenium-catalyzed oxidative cleavage of olefins to aldehydes. Journal of Organic Chemistry, 2001, 66(14):4814-4818.
National Seminar on Science for Sustainable Development, SSD-2020
OP-21
Synthesis and characterization of Cyclometalated iridium complex possessing carbazole containing dendritic ligands
Parmeeta Borthakur and M. Velusamy*
Department of Chemistry, NEHU, Shillong Shillong-793022, Meghalaya, India E-mail: [email protected]
CN donor ligands incorporating pyridine or benzoimidazole N donors and a sterically hinderedcyclometalating aromatic core featuring a polyphenylenephenyl, fluoranthene, ortriphenylene segmentare prepared and successfully converted into heterolepticiridium (III)cyclometalated complexes withacetylacetone auxiliary ligands.Some conjugated dendrons which include phenyl, carbazolyl and fluorene moieties with an alkyl-imidazole segment are constructed via convergent approaches (building from the outside in) with appropriate palladium catalysed cross-coupling reactions (e.g. Suzuki, Heck couplings) of aryl bromide or iodide with aryl boronic acids/esters. The X-ray structure of the complex,derived from a ligand containing afluoranthene fragment, has been solved to unveil the corresponding structure. The results clearlydemonstrate that the nature of the r-coordinating ligand segment plays a key role in dictating theemission profile and peak position, such that the emission hue has been successfully tuned ranging fromgreen to red. Supplementary support of this viewpoint is also rendered by computational (DFT)approaches. Electroluminescent devices fabricated using a complex as dopant in the PVK matrix werefound to exhibit bright greenish yellow emission with promising device characteristics (maximumbrightness 26450 cd m−2 at 30 V and a maximum current efficiency of 40 cd A−1).
Figure: - Synthesis of core molecules
References- 1. M. Velusamyet. al, Dalton Trans.,2007, 3025-3034. 2. M. Velusamyet. al,Organometallics, 2010, 29, 3912-3921.
National Seminar on Science for Sustainable Development, SSD-2020
OP-22
Perovskite-based Photocatalyst
Priyankamoni Saikia, Swapan. K. Dolui*.
Department of Chemical Sciences, TezpurUniversity, Tezpur-784028, Assam, India Email ID: [email protected]
In the emergence of perovskites as light-harvesting materials, Calcium Copper Titanium Oxide (CCTO) has been exploring tremendously for its significant role to act as photocatalyst. Here we report synthesis of a different type of CCTO from citrate precursor’s method. The synthesized powder is characterized different techniques such as Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), solid UV,Energy Dispersive X-Ray (EDX) analysis etc. This synthesized material shows impressive degradation of waste organic dyes under mild condition using household visible light source.
(1) Pal, K.; Mondal, A.; Jana, R.; Ray, P. P.; Gayen, A. Appl. Surf. Sci.2019, 467–468, 543–553. (2) Clark, J. H.; Dyer, M. S.; Palgrave, R. G.; Ireland, C. P.; Darwent, J. R.; Claridge, J. B.; J. Am. Chem. Soc. 2011, 43, 1016–1032. (3) Kushwaha, H. S.; Thomas, P.; Vaish, R. RSC Advances.2015, 87241–87250. (4) Zhang, H.; Chen, G.; Li, Y.; Teng, Y. Int. J. Hydrogen Energy.2010, 35, 2713–2716.
National Seminar on Science for Sustainable Development, SSD-2020
OP-23
Conformation control of N-methyl-N,N'-diacylhydrazines by noncovalent carbon bonding
J.K.R. Deka and B.K. Sarma*
Department of Chemistry, School of Natural Sciences, Shiv Nadar University, UP-201314, E-mail: [email protected] New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India. E-mail: [email protected]
Carbon-mediated non-covalent interactions are important due to the ubiquity of carbon in both chemistry and biology. In recent years, some structural and computational evidence has emerged for non-covalent carbon bonding (C-bond)1 wherein a tetrahedral carbon-bond donors is involved in -hole interactions with C-bond acceptors such as lone pair,1 radical2 or -systems.3The presence of the C-bond is now recognized in small molecules,4 proteins5 and protein-ligand complexes.6However, the evidence of such C-bonds in solution is limited. Herein, for the first time, we strategically designed N-methyl-N,N'-diacylhydrazines where C-bonds can be modulated to control the conformational preferences of N-methyl-N,N'-diacylhydrazines in solution. We show that the most stable trans-cis amide bond rotamer of N-methyl-N,N'-diacylhydrazines is stabilized by an unusual nN (amide) → σ* interaction between the lone pair of an amidic nitrogen atom and a suitably positioned nearby vacant σ* orbital over the expected trans-trans rotamer. Finally, such C- bonds could play an important roles in other N-N bond containing molecules as well, especially in aza-oligomers such as azapeptides, azapeptoidsand their N-methyl derivatives that have N,N'- diacylhydrazinesunits embedded in their structure.
References: 1. D. Mani and E. Arunan, Phys. Chem. Chem. Phys., 2013, 15, 14377–14383. 2. Q. Li, X. Guo, X. Yang, W. Li, J. Cheng and H.-B. Li, Phys. Chem. Chem. Phys., 2014, 16, 11617–11625. 3. D. Mani and E. Arunan, J. Phys. Chem. A, 2014, 118, 10081–10089. 4. S. P. Thomas, M. S. Pavan and T. N. Guru Row, Chem. Commun., 2014, 50, 49–51. 5. V. R. Mundlapati, D. K. Sahoo, S. Bhaumik, S. Jena, A. Chandrakar and H. S. Biswal, Angew. Chem., Int. Ed., 2018, 57, 16496–16500. 6. A. Bauza´ and A. Frontera, Crystals, 2016, 6, 26.
National Seminar on Science for Sustainable Development, SSD-2020
OP-24
ExploitingCu(II)-Fluoride Interaction with Receptor for Sensitive and Selective Recognition of Aqueous Fluoride
Sudhangshu Priya Bharati and Sanjeev P. Mahanta*
Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India E-mail: [email protected], [email protected]
The present work describes anovel methodology that exploits the synergistic interaction of F- and Cu(II) in the recognition of fluoride by a pyrrole-based Schiff base receptorR. The receptor R is selective towards fluoride in chloroform in presence of aqueous Cu(II) ion and vice versa. The binding of fluoride to the receptor in presence of Cu(II) can be assessed through reversible colorimetric change from light yellow to red. In DMSO, although the receptor shows similar colorimetric response as in chloroform, reversibility in sensing is not realized. As suggested by UV- Vis, 1H NMR, 19F NMR, ESR spectroscopy and cyclic voltammetry study and DFT calculations, the plausible sensing mechanism is supposed to be the reduction of Cu(II) to Cu(I) in presence of F- resulting in the formation of [R2CuF]complex. The anion binding event is recyclableon adding
aqueous EDTA solution. The limit of detection (LOD) is calculated to be 5 ppm. This methodology has been successful in detecting fluoride in toothpaste and ground water collected fromthe fluoride affected areas of KarbiAnglong District, Assam.
References:
1. Das R., Bharati S. P, Borborah A., Sarma P. J., Das B., Choudhury S., Chakrabarty G., Mahanta S. P., New J. Chem. 2018, 42, 3758. 2. Black C. B., Andrioletti B., Try A. C., Ruiperez C., Sessler J. L., J. Am. Chem. Soc.1999 , 121, 10438.
National Seminar on Science for Sustainable Development, SSD-2020
OP-25
Climate Change and Its Impact on Biodiversity
Prabhat Chandra Choudhury
Assistant Professor, Department of Chemistry, B.H.College, Howly Howly-781316, Barpeta, Assam, India E-mail: [email protected]
The significant and long-term changes to the climate of a region may be called climate change. In many regions of the world, biodiversity is being reduced by humankind through pollution, changes in land cover and use, invasions of exotic species and possibly climate change. Climate change has created major threats to global biodiversity. It implicates human or anthropogenic activities and this is mainly due to increasing concentrations of green- house gases. Species affected by climate change may respond in three ways: adapt ,move or die out. Local species extinctions or a rapidly affected ecosystem as a whole respectively might move towards its particular- tipping point, thereby probably depriving its services to human society and end up in a global crisis.
As biodiversity underlies all goods and services provided by ecosystems that are crucial for human survival and wellbeing, this paper seeks to examine the potential effects of climate change on biodiversity, its plausible impacts on human society as well as the setting in addressing a global crisis. There are still many gaps in our knowledge of effects of climate change on biodiversity. Urgent and appropriate actions within various scenarios of climate change impacts on biodiversity, especially in tropical regions, are needed to be considered. Foremost a multi sectoral approach on biodiversity issues with broader policies, stringent strategies and programs at international, national and local levels is essential to meet the challenges of climate change impacts on biodiversity.
Keywords : Climate change, biodiversity, ecosystem functioning, global crisis.
National Seminar on Science for Sustainable Development, SSD-2020
OP-26
Watershed Management: A Case Study of Jonai Korong Watershed, North East India
Hemanta Kumar Medhi & Dr. Dhanjit Deka
Department of Geography, B Borooah College, Guwahati, India
A drainage basin is a most suitable geomorphologic unit for organization of all kinds of human activities and natural processes continuing within it. Knowledge of drainage basin characteristics becomes an important pre requisite to evaluate the basin hydrology. The amount of water reaching a stream system is dependent on the morphometry of the basin, total precipitation, losses due to evapotranspiration and absorption by soil and vegetation. Evaluation of morphometric parameters requires preparation of drainage map, contour map, ordering of streams, measurement of catchment area, perimeter, relative relief, relief ratio, length of streams, drainage density, drainage frequency, bifurcation ratio, texture ratio which further helps in understanding the basin environment. Similarly Land use change due to natural causes as well as human interferences is a common phenomena almost each and every river basins of the Northeast India. The changes that have taken place in the basins due to human activities have been accelerated in last few years. Such changes have been identified as the cause of many environmental problems in the region. For this, accurate monitoring and management of land use/ land cover is very much necessary. The present study involves the Remote Sensing and Geographic information System (GIS) analysis technique to evaluate the morphometric analysis of Jonai Korong watershed as well as the monitor the changing pattern of Land Use/Land Cover of the said watershed.
National Seminar on Science for Sustainable Development, SSD-2020
OP-27
Room Temperature Copper-Catalyzed N-Arylations of Hydantoins employingDiaryliodonium Salts
Raktim Abha Saikia and Ashim J. Thakur*
Department of Chemical Sciences, Tezpur University, Tezpur, Assam-784028, India. Email ID:[email protected]
Catalytic synthesis of N-arylatedhydantoin derivatives remains a significant challenge in organic synthesis. Here, we report a Cu-catalysed arylation of hydantoins with diaryliodonium salts and provide a cleaner route for arylation at N3 nitrogen atom in a regioselective manner. The mild catalytic conditions are operationally simple, ligand-free and produce valuable synthetic building blocks in excellent yields.Diaryliodonium salts containing both electron-donating and electron- withdrawing groupsare tolerated under this reaction conditions. Ortho-substituted aryl iodonium salts show good conversion. Further, in a two-step synthesis methodarylation at N1 nitrogen atom is also reported under copper-catalytic pathway.
(1) Konnert, L.; Lamaty, F.; Martinez, J.;Colacino, E.Chemical Reviews, 2017, 117, 13757- 13809. (2) Thilmany, P.; Gérard, P.; Vanoost, A.; Deldaele, C.; Petit, L.;Evano, G. J. Org. Chem., 2018, 84,392-400. (3) Yusubov, M. S.; Maskaev, A. V.; Zhdankin, V. V. ARKIVOC2011, i, 370−409. (4) Merritt, E. A.;Olofsson, B. Angew. Chem., Int. Ed. 2009, 48, 9052-9070.
National Seminar on Science for Sustainable Development, SSD-2020
OP-28
Base Mediated Hydride Eliminating Benzyl Alcohol Oxidation Supported Over Microporous Organic Polymer
Debabrat Pathak and Bipul Sarma Department of Chemical Sciences, Tezpur University, Napaam-784028, Tezpur, India E-mail: [email protected]
Synthesized triazine based amide functionalized microporous organic polymer (MOP-Am2) with extended π-cloud employed to facilitate anaerobic oxidation of benzyl alcohol derivatives to their corresponding aldehydes with 100 % selectivity. Such oxidation reactionusually demands precious active metal catalyst along with oxidant like H2O2, TBHP, O2 etc. We reported that MOP- Am2 is identified as its first kind as metal free organic catalyst promoter to study such oxidation of benzyl alcohol via hydride elimination. Experimental study further proposed the presence of hydride in the reaction mixture with in-situ acetylene reduction reactions supported by computational calculations.
Figure Metal free microporous organic polymer supported anaerobic oxidation of benzyl alcohol derivatives
National Seminar on Science for Sustainable Development, SSD-2020
OP-29 A Study on Government Measures Towards Street Vending as a Sustainable Livelihood Strategy in India at the Advent of Covid -19
Manoj Kumar Das Research Scholar NERIST, Nirjuli, Arunachal Pradesh manojdas567@gmail,com
Street vendors have been playing a significant role in our national economy. In spite of its diversified economic importance especially in UDCs and developing countries like India, this vital sector of informal economy has been facing various challenges whereas government policies for the street traders are inadequate and insufficient over last plan periods. The magnitude of street vendors has been mounting up in urban and semi-urban areas of India in recent decades that pose as an emerging threat for the district administrators and town planners. In this study, a sample of total 400 vendors in Guwahati, Tezpur and Jorhat municipality have been analysed with respect to their livelihood aspects. The present study endeavours to analyse certain aspects of street vendors of three sample cities of Assam and to highlight the government’s measures to rehabilitate the street traders in eking out their livelihood and reduce their economic crisis arising due to Covid-19.
Key words: Street vendors, Informal economy, Covid-19, Livelihood
National Seminar on Science for Sustainable Development, SSD-2020
OP-30 Homogeneous Catalytic Water Oxidation by Nickel Complex with redox active Oxime ligand
Hemrupa Kuilya, Diganta Choudhury*, ApurbaKalita*
Department of Chemistry, B. Borooah College, Guwahati, Assam-781007, India Email: [email protected].
Electrochemical water splitting is an efficient technology for the sustainable energy conversion and many metal complexes involving the first row transition elements as metal centres are engaged in the catalysis of such reactions.1-3In growing competition nickel complexes has also participated as efficient water oxidation catalyst owing to its diverse redox properties and the strong oxidizing power of its high valence states.3-7Based on the above facts, we investigate the electrocatalytic activity of a nickel (II) complex, with oxime-based ligand L1H[L1H = (E)-benzaldehyde oxime]. From the result of the electrochemical studies, it is reveal that complex acts as potent water oxidation catalyst in neutral phosphate buffer.
1. a) Chen, Z.; Meyer, T. J. Angew. Chem. Int. Ed. 2013, 52, 700 –703 b) Zhang,M.-T.; Chen, Z.; Kang, P. ; Meyer, T. J. J. Am. Chem. Soc.2013, 135, 2048 -2051; 2. Zhang, M.; Zhang, M-T.; Hou, C.; Ke, Z-F.; Lu. T-B. Angew. Chem. Int. Ed. 2014, 53, 13042 -13048. 3. Han, Y.; Wu, Y.; Lai, W.; Cao, R. Inorg. Chem. 2015, 54, 5604-5613. 4. Roger, I.; Symes, M. D. J. Am. Chem. Soc.2015, 137, 13980-13988. 5. Wang, J-W.; Zhang, X-Q.; Huang, H-H.; Lu, T-B. Chem.Cat.Chem.2016, 8, 1-8. 6. Wang, D.; Bruner, C. O. Inorg. Chem.2017, 56, 13638−13641. 7. Wang, J-W.; Hou, C.; Huang, H-H.; Liu, W-J.; Ke Z-F.; Lu, T-B. Catal. Sci. Technol., 2017, 7, 5585–5593.
National Seminar on Science for Sustainable Development, SSD-2020
OP-31
Spatiotemporal proteome mapping for organelle-communications using two orthogonal protein labeling & isolation methods
Jyotish Nath, Kimoon Kim* Centre for Self-assembly and Complexity, Pohang University of Science and Technology, Pohang, Republic of Korea Email: [email protected]
Manyimportant cellular processes are regulated by the communication between organelles and these organelles are known to communicate via the proteins.1The proteins involved in the organelle communications can vary based on the condition of the cell, thus they can be found in specific spatiotemporal windows.2 Isolation of the same in multiple target organelles at a specific time is the key step to identify the proteins responsible for a specific communication. The conventional methods for the isolation of proteins meet several drawbacks and render difficulties in providing appropriate information about spatiotemporal origins and this has led scientists to look for more reliable method through different approaches. Recently, spatially resolved protein isolation methods have been demonstrated by proximity-based spatiallabeling oforganelle proteinswith biotin as a chemical handle and the subsequentenrichment of the labeled proteinswith streptavidin (SA)-conjugated beads (SA-Beads).3 Following this result, another group reported 12 15 -1 that cucurbit[7]uril(CB[7])-adamantane (Ad)/ferrocene (Fc) (Ka ~10 -10 M ) shows comparable binding 14 -1 affinity to SA-BT (Ka ~10 M ), thereby demonstrating synthetic ultrastable binding pairs. Using the CB[7]- Fc ultrastable binding pair, plasma membrane proteins were labeledwith Fc and enriched by CB[7]- conjugated beads (CB[7]-beads), which allows us to use CB[7]-Fc pair as a chemical biology tool for protein enrichment.4 In this project, it has been hypothesized that using this two orthogonal methods of labeling and isolation of proteins could be used to identify the proteins responsible for the specific communications.
References:
1. Elbaz, Y.; Schuldiner, M. Trends Biochem. Sci.2011, 36, 616. 2. Bravo-Sagua, R.; Torrealba, N.; Paredes, F.; Morales, P. E.; Pennanen, C.; Lopez-Crisosto, C.; Troncoso, R.; Criollo, A.; Chiong, M.; Hill, J. A.; Simmen, T.; Quest, A. F.; Lavandero, S. Int. J. Biochem. Cell B.2014, 50, 55 3. Rhee, H. W.; Zou, P.; Udeshi, N. D.; Martell, J. D.; Mootha, V. K.; Carr, S. A.; Ting, A. Y. Science2013, 339, 1328 4. Lee, D. W.; Park, K. M.; Banerjee, M.; Ha, S. H.; Lee, T.; Suh, K.; Jung, H.; Kim, J.; Selvapalam, N.; Ryu, S. H.; Kim, K. Nat. Chem.2011, 3, 154
National Seminar on Science for Sustainable Development, SSD-2020
OP-32
Homogeneous Electrocatalytic Water Oxidation by Copper (II) Complex with Redox Active Ligand in Neutral Phosphate Buffer
Pranjal Das, Apurba Kalita*,
Department of Chemistry, B. Borooah College, Guwahati, Assam-781007, India
E-mail ID: [email protected]
Energy demand and environmental concerns are driving the development towards the large production of clean energy. One such sustainable alternative pathway is the production of hydrogen or oxygen by the means of artificial photosynthesis1. In nature, Chemical energy is produced by the photosynthetic system using solar energy. In the conversion of solar energy to chemical energy, water is used as raw material and it is catalytically oxidized to O2. The oxidation of water is catalysed by the Mn4CaO5 cluster of photosystem II (PS II) and produces O2 at rates estimated at 100-400 S-1. By inspiring from nature, constructing an artificial photosynthetic device is the primary goal for the scientific community to solve the world energy problem2, 3. Many research groups have developed different water oxidation catalysts, which are of Ru, Ir, Mn, Co and Fe-based metal complexes4. Among them, copper (II) - base water oxidation catalyst (WOC) has been reported as competent candidates with successive improvements of catalytic activities5. In this regard, we investigate the electrocatalytic water oxidation of a copper (II) complex, [Cu(L1)(L2)(H2O)](ClO4)2, with bipyridine (L1) and Bis-(2-aminoethyl) amine (L2) as ligands at neutral phosphate buffer. From the result of the electrochemical studies, it reveals that the complex is a potent water oxidation catalyst exhibiting high catalytic efficiency.
[Cu(L )(L )(H O)](ClO ) 1 2 2 4 2 + - H2O 4H + O + 4e electrocatalysis 2
References:
1. Liao, C. H.; Huang, C. W.; Wu, J. C. S. Catalysis, 2012, 2, 491. 2. Akihiko K.; Yugo M., Chem. Soc. Rev. 2009, 53, 253. 3. Duan, L.; Bozoglian, F.; Mandal, S.; Stewart, B.; Privalov, T.; Llobet, A.; Sun, L. Nature Chemistry. 2012, 4, 418-423 4. Liu, X.; Wang, F. Coordination Chemistry Reviews. 2012, 256, 1115-1136 5. Roger, M. A. Shipman, M. D. Symes, Nat. Rev. Chem. 2017, 1, 003
National Seminar on Science for Sustainable Development, SSD-2020
PP-1
Exploring the Reactivity of Carbene Supported DiboraanthraceneTowardsDihydrogen Activation
ChayanikaKashyap, Ankur K. Guha*
Advanced Computational Chemistry Centre, Department of Chemistry, Cotton University, Panbazar, Assam, India-781001 *E-mail: [email protected]
Quantum chemical calculations have been carried out on some N-heterocyclic carbene
(NHC) stabilized boraanthracenes to investigate their possibility to act as H2 activators. Different coordination modes such as normal, abnormal and remote NHC are considered. Moreover, a 1,3,2,5- diazadiborinine molecule, which is experimentally known to activate H2 has also been considered for comparison. All the studied systems have a lower HOMO-LUMO gap than this molecule, an important factor for rendering higher reactivity. Quasiclassical trajectory for the reaction between H2 and these molecules indicates a single dynamically concerted step. Electronic structure analysis reveals synergism between donation and back donation in the activation process. The effect of substituents has also been studied which reveals that electron withdrawing substituents increase the activation barrier while electron donating substituents decrease it. With remote NHC stabilized boraanthracenes, it may be possible to achieve a low kinetic barrier and thermodynamic reversibility for activation of H2.
References [1] P. Sabatier, Ind.& Eng. Chem. 18 (1926) 1005-1008. [2] (a) D. M. Heinekey, W. J. Oldham, Chem. Rev.93 (1993) 913-926; (b) J. F. Hartwig, Organotransition Metal Chemistry: From Bonding to Catalysis; University Science Books: Mill Valley, CA, (2010); (c) R. H. Crabtree, Chem. Rev. 116(2016) 8750-8769. [3] (a) P. P. Power, Nature463 (2010) 171-177; (b) T. Chu, G. I. Nikonov, Chem. Rev. 118 (2018) 3608-3680.
National Seminar on Science for Sustainable Development, SSD-2020
PP-2
Photophysical studies of three green fluorescent protein chromophore analogs Sheikh Abdullah Research scholar, Department of chemistry, Cotton University, Guwahati - 781001
Green fluorescence protein (GFP) is a fluorescent protein present in the jelly fish Aequorea victoria available in the sea water present in the range from Alaska to central California. The chromophore responsible for the intrinsically high fluorescence of GFP is a heterocyclic molecule – imidazolin-5-one which is present at the centre of the protein coat of GFP. Based on the structure of the imidazolin-5-one chromophore of GFP, three analogous molecules have been synthesized and successfully characterized and their preliminary photophysical properties have been studied and discussed. All the molecules have molar absorption coefficient higher than that of GFP, but the intriguing observation is that they have fluorescence quantum yield much less than that of GFP which suggest the presence of a dominant deactivation channel in the excited state of these molecules. Theoretical calculations on the potential energy surface of one of the three molecules very nicely depict internal conversion through conical intersection of the ground and first excited singlet states.
References:
1. Altoe P., Bernardi F., Garavelli M., OrlandiG. and Negri F. Journal of American Chemical Society(2005) 127, 3952. 2. Baldridge A., Samanta S. R., Jayaraj N., Ramamurthy V. and Tolbert L. M. Journal of AmericanChemical Society (2011) 133, 712. 3. Rajbongshi B. K., Sen P. and Ramanathan G. Chemical Physics Letters (2010) 494, 295.
National Seminar on Science for Sustainable Development, SSD-2020
PP-3
Study on Ambient Air Quality at Guwahati, Assam, India
Nabajit Barman & Bijoy S Goswami
Department of Chemistry, B. Borooah College, Guwahati-781007 www.bborroahcollege.ac.in, [email protected]
Urban air pollution is a worldwide phenomenon and each situation has individual characteristics related to the local conditions. Air masses always contain many pollutants in differing amounts, including both particulate matter (PM) and gaseous pollutants. Increasing amounts of potentially harmful gases and particles are being emitted into the atmosphere on a global scale, resulting in damage to human health and the environment.Due to rapid population growth, urbanization and industrialization in recent decades, the air pollution has globally been recognized as a serious problem with its short-term and long-term impacts on environment and human health. Air pollution is considered to be primarily major urban pollution problem now days in Guwahati city as the rate of urbanization increases. The vehicular emissions and wind dust contributes a major share in deteriorating the air quality of Guwahati. The present study is carried out at various locations of Guwahati such as Chandmari, Adabari, Gauhati University, Tetelia and Lokhra by undertaking these prime objectives (i)Monitoring of PM10 and PM2.5(ii)Monitoring of the concentration of SO2 and NOx(iii)Monitoring of Pb, As and Ni content in particulate matter. The samples are analyzed for various parameters using standard methods as per central pollution control board (CPCB) guideline. The results revealed that all the parameters such as PM10, PM2.5, SO2 and NO2 are within the CPCB specified limit. The PM10 ranged from 52.2 (GU) to 86.2 (Lokhra). The PM2.5 ranged from 21.2 (GU) to 44.3(Adabari). The SO2 ranged from 7.8(GU) to 14.1(Lokhra) while NO2 ranged from 9.2 (GU) to 18.2(Lokhra). Among heavy metals, the Pb content varied from <0.2 to 0.28μg/m3 in PM10 while <0.2 to 0.28μg/m3 in PM2.5. The Ni content ranged from <2.0 to 3.6 in PM10 while in pm2.5 it ranged from <2.0 to 2.8. The As content is appeared as below detectable lavel. The present study conclusively showed that the ambient air quality is mostly contaminated with particulate matter. Since the major industries in Guwahati is very less hence the vehicular emissions, earth cutting from surrounding hill, bad condition of road, developmental activities are the principal source for the contamination of overall city’s environment.
National Seminar on Science for Sustainable Development, SSD-2020
PP-4
REMOVAL OF FLUORIDE FROM AQUEOUS SOLUTION
USING FISH SCALE
Dona Deb & Bijoy S Goswami
Department of Chemistry, B. Borooah College, Guwahati-781007 www.bborroahcollege.ac.in, [email protected]
The level of fluoride in drinking water is a very important physicochemical factor, which must be considered when assessing water quality for human consumption. It is known that its low concentration as well as its excess causes health problems to the human beings. More than 25 nations of the world including India suffer from the contamination of fluoride in drinking water. Orissa is one of the states where 10 out of the 30 districts are suffering from fluoride contamination. Depending on the concentration and consumption of its total amount, fluoride ions in water have beneficial as well as detrimental effects. The consumption of drinking water with a fluoride level greater than about 4 mg L-1 causes prevailing dental fluorosis in the population, and the chronic consumption of water containing high levels of fluoride between 4 and 15 mg L-1 provokes skeletal fluorosis that is associated with serious bone abnormalities. On the other hand, if the concentration of fluoride is below 0.5 mg L-1, the incidence of dental caries increases considerably.The present study is based on the removal of fluoride using low cost adsorbent such as Fish Scale Powder (FSP). The batch adsorption experiments were carried out to find the fluoride adsorption capacity of FSP from aqueous solution.The major objectives of the present study are adsorbent dose, pH variation, effect of agitation time effect of different concentration and the different isotherm model study.The study of effect of agitation time reveals that the removal of fluoride increases in the first 30 minutes which is 96.7% and then becomes almost constant to 97.5% .This is because number of available sites for adsorption decreases with increase in time. Dose study reveals that the percentage removal of fluoride till 0.3g/l dose of FSP increases very rapidly. After that it becomes constant. pH study reveals that the removal is maximum at pH 6 (~93.1%) and is minimum at pH 14.The effect of concentration study reveals that as the concentration increases with the decrease of fluoride removal percentage gradually.The present study also satisfied the adsorption model study such as Langmuir, andFreundlich.The present study conclusively shows that Fluoride can be effectively removed from aqueous solution byFish Scales.
National Seminar on Science for Sustainable Development, SSD-2020
PP-5
Organic Manure Formulation Using Eri-Muga,Cow And Poultry Excreta
Kaushiki Deka & Bijoy S Goswami
Department of Chemistry, B. Borooah College, Guwahati-781007 www.bborroahcollege.ac.in, [email protected]
The rigorous use of chemical fertilizers has led to the deterioration of the dynamic equilibrium of soil, flora and fauna ecosystems as well as water streams contamination. Hence, the need for sustainable fertilization with minimal environmental impact has given rise to the search for alternative fertilizer sources for use in agriculture. This has generated increasing interest in renewable feedstock from organic waste since the past decade. The word "organic" pertains to the use of non-chemical fertilizers as manure and compost and the word "manure" refers to any natural substance for fertilizing the soil. Organic manure is nutrient derived from organic sources like animal waste, vegetable compost, agricultural residues, etc. Basically they are natural materials that decay and get mixed with the soil thereby increasing its fertility. The study has been done to find the potential use of seriwaste. chicken excreta and cow excreta as organic manure. The principal objectives of the present study are (i) Preparation of organic Manure using Ari, Muga, Cow and Chicken waste (ii) Characterization of waste for major Nutrients contents. Cow and Poultry excreta were collected from Cow and chicken farms respectively. The Ari –Muga excreta were collected from sericulture firm Directorate of Agriculture, Khanapara, Guwahati. The results of the present study are pH : 6.3 (Muga excreta) - 7.5 (Cow excreta); N: 0.014% (Muga) – 0.084 %(Chicken); P : 0.89 ppm (Muga) – 1.7 ppm (Chicken); K: 111ppm (Muga) – 374 ppm(Chicken); B: 4.1 ppm(Chicken) – 6.6 ppm(Cow); Ca2+ : 0.08ppm (Cow) – 0.57ppm(Muga); Mg2+ : 0.034ppm(Cow) – 0.46ppm (Muga); Na+ : 25.3ppm (Muga) – 60.1ppm(Chicken). From these results it can be concluded that seriwaste, poultry waste (chicken excreta) as well as cow dung contains various nutrients which could be put into use in agricultural activities as fertilizer using proper management techniques to avoid some of its detrimental effects. It is an eco-friendly technology.
National Seminar on Science for Sustainable Development, SSD-2020
PP-6
Label-free Sensing of Abasic DNA using Pyrenylamido Triazolyl Aromatic Amino Acid Scaffold as AIE probe
Hiranya Gogoi, Subhashis Jana and Subhendu Sekhar Bag*
Bio-organic Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Guwahati- 781039. Tel: +91-361-2582324; Fax: +91-361-2582349. Email: [email protected] / [email protected]
We report a label-free strategy for switch-on sensing of abasic DNA using aggregation- induced emission (AIE) probe, pyrenylamido triazolyl aromatic amino acid scaffold (PyAm- ArTAA). In aqueous media and buffer the probe molecule aggregates through the electrostatic as well as hydrophobic π-π stacking interaction resulting in strong fluorescence emission. Thus, the probe is found to be useful in sensing of an abasic site opposite to adenosine (A) base of a T-rich 13-mer DNA via an enhancement of fluorescence intensity. Intercalative stacking interaction of pyrenyl unit within the minor groove and alongside the abasic site opposite of base A possibly play an essential role in the success of label-free sensing of abasic DNA by the probe.
Scheme 1. The chemical structure of the AIE probe and the schematics of the concept of binding of the probe PyAm-ArTAA to an abasic site opposite to A base (X = A).
References
1. Bag, S. S.; Pradhan, M. K.; Talukdar, S. J. Photochem. Photobiol. B. 2017, 173,165. 2. Bag, S. S.; Jana, S. New J. Chem. 2017, 41, 13391. 3. Bag, S. S.; Kundu, R.; Jana, S. Tet. Lett. 2013, 54, 2627.
National Seminar on Science for Sustainable Development, SSD-2020
PP-7
Mn(III) Porphyrins For Photo-induced in vitro Anticancer Activity
Bidisha Bora and Tridib K. Goswami,
Department of Chemistry, Gauhati University, Guwahati-781014, Assam, India. e-mail id: [email protected]
The use of metalloporphyrins in the field ofphotodynamic therapy (PDT) has been remarkably evolving in recent years. In this work, we present the synthesis and characterization of five Mn(III) porphyrinsviz.[Mn(III)TPP(H2O)2] (1), [Mn(III)TMeP(H2O)2] (2), [Mn(III)TMP(H2O)2] (3), [Mn(III)(ClTPP)(H2O)2] (4) and [Mn(III)(FTPP)(H2O)2](5) and examine their photo-induced anticancer activity.The respective free base porphyrins display characteristic Soret and Q-bands in UV-Visible which show significant shifts on metallation. The complexes1-5 were found to be stable over a period of 24h in DMSO-DMEM (1:1). The solid state structures of all the complexes 1-5 were authenticated by single crystal X-ray diffraction method. Cyclic voltammetry studies showeda quasi-reversible Mn(II)/Mn(III) peak in the region of ~ -0.2 V vs. n Ag/AgCl reference electrode in DMF-0.1M [Bu 4N](ClO4). The Mnporphyrins were found to be avid binder to Human Serum Albumin (HSA) as evident from fluorescence-quenching experiments which could potentially transport them in blood plasma. The metalloporphyrins exhibit excellent in vitrophotocytotoxicity when exposed to low energy visible light (400-700 nm).
ROS
Cellular
apoptosis
Figure: Mode of action of PDT.
References
(1)Rajora, M. A.; Lou, J. W. H.; Zhang, G. Chem. Soc. Rev.2017, 46, 6433-6469. (2)Castano, A. P.; Demidova, T. N.; Hamblin, M. R. Photodiagn. Photodyn. Ther. 2004, 1, 279-293. (3)Wang, Y.; Liu, Y.; Li, G.; Hao, J. Langmuir2014, 30, 6419-6426. (4) Walker, N.; Stuart, D. ActaCrystallogr. 1983, A39, 158-166. (5)Hashemi, M.; Solati, Z.; Mohammadpour, P. J. Porphyrins Phthalocyanines2013, 17, 1204- 1208.
National Seminar on Science for Sustainable Development, SSD-2020
PP-8
Structurally characterized Cu(II)-flavonoid complexes with potential biological application Namisha Das, Tridib K. Goswami, Department of Chemistry, Gauhati University, Guwahati-781014, Assam, India E-mail ID: [email protected]
The clinical success in the field of metal based anticancer agents was initiated by cisplatin and its next generation drugs.1 But, due to their high intrinsic toxicity and significant side effects limit their use in clinics and that is why only used in combination therapy with other organic anticancer drugs.2-4 The design of drugs for cancer treatment with novel mode of action stimulated the exploration of other metal based anticancer agents in the field of Photo-activated Chemotherapy (PACT).5 The ability to coordinate various organic compounds of choice to transition metals and their tuneable redox activity gives immense opportunities to design and develop such drug candidates.6-8 Herein, we present the synthesis and physicochemical characterization of six novel assemblies of Cu(II) with flavonoids and ancillary aromatic chelators viz. [Cu(L1)(L2)](ClO4) where, L1=1,10-phenanthroline (phen, 1-3), 2-(anthracen-1-yl)-1H- imidazo[4,5-f][1,10]phenanthroline (aip, 4-6) and L2=3-hydroxy flavone (1, 4), 4-Fluoro-3-hydroxy flavone (2, 5), 2,6-Difluoro-3-hydroxy flavone (3, 6). All the prepared complexes were characterised by UV-Vis, FT- IR, elemental analysis, fluorescence spectroscopy and magnetic susceptibility measurements. Solid-state structure of complex 1 was determined using single crystal X-ray diffraction method. The complexes were found to have moderate binding propensity for human serum albumin (HSA) and calf thymus (ct-DNA) which indicate their potential biological application.
Scheme: Schematic representation of synthesized Cu(II)-flavonoid complexes
References: 1. Maity, B.; Chakravarty, A. R. Indian J. Chem. Sect A. 2012, 51, 69-82. 2. Allardyce, C. S.; Dyson, P. J. Dalton Trans. 2016, 45, 3201-3209. 3. Wheate, N. J.; Walker, S.; Craig, G. E.; Oun, R. Dalton Trans. 2010, 39, 8095-8113. 4. Halevas, E.; Mavroidi, B.; Antonoglou, O.; Hatzidimitriou, A.; Sagnou,M.; Pantazaki, A.A.; Litsardakis, G.; Pelecanou. M. Dalton Trans. 2020, 1-42. DOI: 10.1039/C9DT04540F 5. Naik, A.; Rubbiani, R.; Gasser, G.; Spingler, B.; Angew. Chem. 2014, 126, 7058-7061. 6. Bonnet, S. Dalton Trans. 2018, 47, 10330-10343. 7. Mitra, K.; Lyons C. E.; Hatrman, M. C. T. Angew. Chem. Int. Ed. 2018, 57, 10263-10267. 8. Monro, S.; Colon, K. L.; Yin, H.; Roque, J.; Konda, P.; Gujar, S.; Thummel, R. P.; Lilge, L.; Cameron C. G.; McFarland, S. A. Chem. Rev. 2019, 119, 797-828.
National Seminar on Science for Sustainable Development, SSD-2020
PP-9
The Preparatory Choreography During O2 Binding and Origins of the Necessity for Two Protonation Pathways in the Catalytic Cycle of P450
Surajit Kalitaa, Sason Shaik*band Kshatresh Dutta Dubey*a
a. Department of Chemistry & Center for Informatics, Shiv Nadar University, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh 201314, India b. Institute of Chemistry, The Hebrew University, Jerusalem 9190400, Israel *[email protected], [email protected]
We have used MD simulations and QM/MM calculationsto study the preparatory-half of the catalytic-cycle of CYP450 enzymes for two distinct classes considering the best model system for each class;
CYP450CAM and CYP450BM3.Our study includes the unexplored area of the preparatory half: (a) the O2- entrance and -binding to form the oxyferrous species, as a function of O2-concentration/(pressure), and (b) the protonation steps which eventually lead to the formation of the ultimate active species, Compound I. Two very basic and paradigm-shifting findings emerge: (a) the O2-concentration/(pressure) required for O2- binding must be neither high nor low. The binding is ushered by substrate choreography, which is guided by the moderate O2-pressure and strategic protein residues (Arg112 and Phe87, respectively) that block the substrate approach to the heme, thus enabling O2 accumulation near iron; and (b) the formation of water channels, which elicit the protonation steps are different for the respective formation of Compound 0 and Compound I.Formation of Compound 0 occurs via the channels that are formed by breakage of the salt- bridges holding the propionate side-chains of the porphyrin, while formation of Compound I takes place via the traditional acid-alcohol pairs (Asp 251/Thr 252 in CAM; Glu 267/Thr 268 in BM3). The location of acidic ammonium-groups (Lys69 in CYP450BM3 and Arg299 in CYP450CAM) near the propionate side-chains is generally conserved in the CYP450 family. Hence, this study highlights the evolutionary need for at least two alternative water-channels, to tune the P450 nanomachine so it can complete the two steps of the protonation and form ultimately Compound I.
National Seminar on Science for Sustainable Development, SSD-2020
PP-10
Unconventional Supramolecular Contacts involving nitrile in Pyridine based Ni(II) and Zn(II) Coordination Compounds: Antiproliferative Evaluation and Theoretical Studies
Amal Dasa, PranaySharmaa, HirenNatha, Manjit K. Bhattacharyyaa*
aDepartment of Chemistry, Cotton University, Guwahati-781001, Assam, India *Corresponding authors E-mail: [email protected]
The construction of metal-organic supramolecular architectures depends on various synthetic factors such as the nature of the metal centers [1], counter ions [2] and the reaction conditions [3]. In this respect, selection of suitable organic moieties plays a significant role for assemblingarchitectures of desired dimensionalities [4]. Transition metal complexes of pyridine dicarboxylates and pyrazole-based ligands have been extensively used in recent times to exploitthe supramolecular assemblies in coordination compounds [5]. In addition to the conventional non- covalent interactions, unconventional contacts also stabilize supramolecular architectures and are therefore of particular interest from the crystal engineering viewpoint[6]. In the present work, we have synthesised and characterized two new coordination complexes viz., [Ni(2,6-PDC)(Hdmpz)(H2O)2]∙H2O (1) and [Zn(3-CNpy)2Cl2] (2) (2,6-PDC = 2,6- pyridinedicarboxylate, Hdmpz = 3,5-dimethylpyrazole, 3-CNpy = 3-cyanopyridine).Crystal structure analysis of compounds 1 and 2 revealsthe presence of anion–pi, energetically significant CN⋯CN and unconventional C–H⋯pi(nitrile) interactions in the supramolecular assemblies.We have further theoretically explored these interactions using DFT calculations, MEP and QTAIM analysis.The in vitroantiproliferative activities of the compounds have been explored in DL cancer cell lines considering cytotoxicity, apoptosis, molecular docking and pharmacophore features.
References 1. (a) Bhattacharyya,M. K.;Saha, U.; Dutta, D.; Frontera, A.; Verma, A. K.; Sharma, P.; Das, A. New J. Chem. 2020, 44, 4504; (b) Sharma, P.; Gogoi, A.; Verma, A. K.; Frontera, A.; Bhattacharyya, M. K.New J. Chem. 2020,44, 5473. 2. (a) Dutta, D.; Nath, H.; Frontera, A.; Bhattacharyya, M.K. Inorg. Chim.Acta2019, 487, 354; (b) Bhattacharyya, M.K.; Saha, U.; Dutta, D.; Das, A.; Verma, A.K.; Frontera, A.RSC Adv.2019, 9, 16339. 3.Bhattacharyya, M. K.; Gogoi, A.; Chetry, S.; Dutta, D.; Verma, A. K.; Sarma, B.; Franconetti, A.;Frontera, A. J. Inorg. Biochem.2019,200,110803. 4.Nath, H.; Dutta, D.; Sharma, P.; Frontera, A.; Verma, A. K.; Oliver, M. B.; Devi, M.; Bhattacharyya, M. K. Dalton Trans. 2020,49,9863. 5.Gogoi, A.; Islam, S.M.N.; Frontera, A.; Bhattacharyya, M.K. Inorg.Chim.Acta, 2019,484, 133. 6. Das, A.; Sharma, P.; Frontera, A.; Verma, A. K.; Oliver, M. B.; Hussain, S.; Bhattacharyya, M. K. J. Mol. Struct.2020, 1223, 129246.
National Seminar on Science for Sustainable Development, SSD-2020
PP-11
Anion recognition aptitude of a pair of non-symmetrical tripodal receptor in both solid state and solution phase
Nilotpal Borah and Gopal Das
Department of Chemistry, Indian Institute of Technology Guwahati, Assam-781039 Email: [email protected]
Two novel non-symmetric tripodalreceptors (L1 and L2) have been synthesized, and their competitive binding aptitude in both solid state and solution phase has been reported.The receptors
L1and L2 are decorated with two similar benzimidazole arms and the third arm in case of L1is modifiedwith an amide linked nitrophenyl moiety while the receptor L2possesses a naphthyl functionalized third arm to get assistance in photophysical properties. In the solid state, two protonated units of L1bind one sulfate and two bisulfates in unison.The asymmetric unit of L2 encompasses two molecules of the non-symmetrical receptor which bind two molecules of sulfate anion. In both instances, the benzimidazole –NHs are found to be the potent source of hydrogen bond donors. The neutral receptorL1exhibits selectivity towards the fluoride ion inducing a naked eye colorimetricchange whereas L2 acts as a fluorescent chemosensor for fluoride ion with a remarkable red shift of 100 nm. The recognition behaviour of the probe L2 towards fluoride ion using emission spectroscopy is accompanied by ratiometric change with a visual change in colour from violet to cyan under UV light.
References: 1. N. Borah, A. Gogoi and G. Das, Supramol. Chem., 2016, 28, 275-283. 2. N. Borah, B. Nayak, A. Gogoi and G. Das,New J. Chem., 2019,43, 16497-16505.
National Seminar on Science for Sustainable Development, SSD-2020
PP-12
Pd3Cu0.5Ni0.5 Nanowire Networks Stabilized on Carbontowards Boosting Dioxygen Reduction in Alkaline Electrolyte
Rashmi Chetry, BirajJyoti Borah, Pankaj Bharali* Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India *E-mail: [email protected] 4 Developments of high performance non-Pt electrocatalysts for oxygen reduction reaction (ORR) are highly demanded for the production of renewable hydrogen energy. Herein, we report the synthesis of Pd3Cu0.5Ni0.5 nanowire networks (NNWs) stabilized on carbon support by using a one- step solvothermal method without using any structure directing agent or surfactant. Electrochemical properties of the synthesized NNWs, such as electrochemically active surface area (ECSA), ORR activity, durabilitywere assessed by cyclic voltammetry (CV), rotating disk electrode (RDE) and chronoamperometry (CA) experiments. Size, morphology and dispersion pattern of these electrocatalysts (ECs) on conductive carbon were characterized by TEM, HRTEM. The composition of the NNWs was identified by ICP-OES and EDX techniques. Experimental results show that
Pd3Cu0.5Ni0.5/C, with a higher ECSA favours four electron reduction pathways, shows highest current density for ORR as evident from Fig. 1 and is superior to commercially available Pt/C and Pd/C catalysts. The unique nanowire network structure of the alloy offers a stable electronic coupling between the carbon matrix and Pd3Cu0.5Ni0.5 boosting the ORR performance in alkaline electrolyte.
Fig.1.Comparison of rotating rate-dependent ORR polarization curves for different ECs in 0.1 M KOH electrolyte at 1600 rpm.
References: 1. Gao, D., Zhou, H., Cai, F., Wang, J., Wang, G., & Bao, X. Pd-containing Nanostructures for
Electrochemical CO2Reduction Reaction. ACS Catalysis, 8(2): 1510-1519, 2018.
2. Borah, B. J., Yamada, Y., & Bharali, P. Unravelling the Role of Metallic Cu in Cu-CuFe2O4/C Nanohybrid for Enhanced Oxygen Reduction Electrocatalysis. ACS Applied Energy Materials, 3(4): 3488-3496, 2020. 3. Borah, B. J., Saikia, H., Goswami, C., Hazarika, K. K., Yamada, Y., & Bharali, P. Unique Half Embedded/Exposed PdFeCu/C Interfacial Nanoalloy as High-Performance Electrocatalyst for Oxygen Reduction Reaction. ChemCatChem, 11(15): 3522-3529, 2019.
National Seminar on Science for Sustainable Development, SSD-2020
PP-13
Interfacial CuCo/CuOx-Co3O4/C Nanohybrids as Highly Stable Electrocatalysts for Oxygen Reduction Reaction
Suranjana Patowary, Biraj Jyoti Borah and Pankaj Bharali* Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India E-mail: [email protected] Owing to the slow kinetics of oxygen reduction reaction (ORR) and Pt/C being the state-of-the-art electrocatalyst, the search for earth-abundant alternatives have been a hotspot of research. Herein, we report a one-step solvothermally synthesized, non- noble CuCo/CuOx-Co3O4/C with metal-oxide interface, exhibiting ~98% retention of current after a chronoamperometry (CA) test of 7200 s. Reducing agent used was hydrazine-hydrate. TEM images Figure 1: A schematic of ORR on CuCo/CuOx-Co3O4/C NHs reveal spherical nanohybrids and its comparison with various electrocatalysts and (NHs) in the range of 20 nm, commercial Pt/C. partially embedded into the Vulcan carbon support which imparts stability to the architecture. XP spectra reveals co-existence of multi-valent Cu0/+2 and Co0/+2/+3 which serves as a good redox system for better electron transport and conductivity. Electrochemical activity toward ORR was studied by performing cyclic voltammetry (CV) and rotating disk electrode-linear sweep voltammetry (RDE-LSV) at 400, 900, 1600, 2500, 3600 rpm. The ORR scheme and comparison in terms of onset potential, half-wave potential, current-density and stability are included in Figure 1. The as-synthesized CuCo/CuO- -2 Co3O4/C NH outperforms commercial 20 wt% Pt/C by delivering a current-density of 4.9 mA cm compared to 3.8 mA cm-2 of Pt/C. Koutecky-Levich (K-L) plots revealed first-order kinetics and a 4e- reaction-pathway. Hence, this highly competing candidate with high current retention can strive path for better understanding of the importance of optimum chemical and electronic synergy among carbon support and metallic-oxidic interfacial facets to design substitutes for Pt/C as new commercial electrocatalyst. References: 1. Borah, B. J.; Yamada, Y; Bharali, P. Unravelling the Role of Metallic Cu in Cu-CuFe2O4/C Nanohybrid for Enhanced Oxygen Reduction Electrocatalysis. ACS Appl. Energy Mater. 2020, 3(4), 3488-3496 2. Hou, J.; Sun, Y.; Wu, Y.; Cao, S.; Sun, L. Promoting Active Sites in Core–Shell Nanowire Array as Mott–Schottky Electrocatalysts for Efficient and Stable Overall Water Splitting. Adv. Funct. Mater. 2018, 28, 1704447 3. Jin, H.; Wang, J.; Su, D.; Wei, Z.; Pang, Z.; Wang, Y. In situ Cobalt−Cobalt Oxide/N-Doped Carbon Hybrids as Superior Bifunctional Electrocatalysts for Hydrogen and Oxygen Evolution. J. Am. Chem. Soc. 2015, 137, 2688−2694
National Seminar on Science for Sustainable Development, SSD-2020
PP-14 Synthesis, Structure and Photo-triggered in vitro anticancer activity of Ni(II) complexes of curcumin Atrayee Banaspati, Tridib K. Goswami, Department of Chemistry, Gauhati University Guwahati-781014, Assam, India. E-mail: [email protected]
Complexes of Ni(II) curcumin viz. [Ni(cur)(L)2](OAc), where Hcur is curcumin and L is 1,10- phenanthroline (phen, 1), dipyrido[3,2-d:2’,3’-f]quinoxaline (dpq, 2), dipyrido[3,2-a:2’,3’-c]phenazine (dppz, 3) were prepared and characterized by various physicochemical methods. Light-induced in vitro anticancer activity of all the prepared complexes were studied. Three nickel(II) complexes containing acetylacetonato (Hacac) ligand, viz.[Ni(acac)(L)2](OAc) (4-6) where L is phen (in 4), dpq (in 5), dppz (in 6) were prepared and used as controls. Single crystal X-ray diffraction study of complex 4 revealed that it has an octahedral
NiN4O2 geometry around the metal centre. Curcumin Complexes (1-3) showed an intense curcumin-based band at ~440 nm in DMSO-Tris-HCl buffer (pH=7.2) (1:9 v/v) which masks the nickel centered d-d band. Complexes 1-3, i.e. the curcumin comlexes were found to be redox inactice at the nickel centre, whereas the acetylacetonato complexes (4-6) displayed an irreversible cyclic voltammetric responses in DMF-0.1 M TBAP at ~1.00 V vs. Ag/AgCl reference electrode. All the prepared complexes bind to human serum albumin (HSA) and calf thymus DNA (ct-DNA) with considerable affinity. The Ni(II) curcumin complexes display highly significant in vitro light-induced cytotoxicity in HeLa (human cervical carcinoma) and A549 (lung cancer cells) with very low dark toxicity. The complexes were found to be much less toxic to immortalized lung epithelial normal cells (HPL1D).Confocal microscopic images of complexes 2 and 3 showed their primary cytosolic localization in the A549 cells. The complexes are capable of generating reactive oxygen species (ROS) on electronic excitation in visible region. The mechanism of cell death is mainly apoptosis in nature showing arrest of G2/M phase of cell cycle progression in A549 cells under visible light exposure.
References: (1) Oun, R.; Moussa,Y. E.; Wheate,N. J. Dalton Trans.2018, 47, 6645. (2) Salehi, B.; Stojanovic-Radic, Z.; Matejic, J.; Sharifi-Rad, M.; Kumar, N. V. A.; Martins, N.; Sharifi- Rad, J. Eur. J. Med. Chem.2019, 163, 527. (3) Saad, E. A.; Hassanien, M. M.; El-Iban, F. W.; Biochem. Biophys. Res. 2017, 484, 579.
National Seminar on Science for Sustainable Development, SSD-2020
PP-15
Structural and Functional Changes of Protein β-Lactoglobulin Under Thermal and Electrical Processing Conditions
Indrani Baruah, Gargi Borgohain*
Department of Chemistry, Cotton University, Guwahati-781001, India e-mail: [email protected]
In the present study we have tried to explore the effect of static external electric field of strength 3.0V/nm on the conformational changes adopted by the protein β-Lactoglobulin [1]. We have chosen different temperatures viz. 300K, 400K and 450K to evaluate the temperature dependent effect of electric field [2]. We have observed that combined effect of high temperature and static external electric field show significant changes on the structural conformation of the protein which in turn may affect the functional properties of the protein. Calculations of root mean square deviations reveal that both helical and β-sheet regions of the protein are noticeably affected at high temperature. We have used solvent accessible surface area (SASA) and dipole moment values to explain that there is a change in hydrophobicity of the protein surface due to presence of external electric field [3]. The study reveals that electric field in combination with high temperature can be used to alter the conformation of the protein and the effect of external electric field is more pronounced at high temperature than that of low temperature. The study provides a better understanding of the conformational changes adopted by the protein under the stress of external electric field and high temperature and provide guidance to choose optimum conditions for processing without loss of nutritional properties.
References: 1. Sawyer, L., Kontopidis, G., and Wu, S.Y. 1999. International Journal of Food Science and Technology. 34, 409-418. 2. Singh, A., Orsat, V., and Raghavan, V. 2013. Biomolecules. 3, 168-179. 3. Baruah, I and Borgohain, G (Manuscript Submitted).
National Seminar on Science for Sustainable Development, SSD-2020
PP-16
Effective modulation against amyloid aggregation of hIAPP using modified stapled peptides
SouravKalita, SujanKalita and Bhubaneswar Mandal* Laboratory of Peptide and Amyloid Research, Department of Chemistry, Indian Institute of Technology Guwahati, Assam- 781039, India. [email protected]
The polypeptide, amylin or hIAPP plays a significant role in glucose metabolism along with insulin hormone. However, at physiological condition, it undergoes amyloid formation and involve in destruction of pancreatic β-cell dysfunction, which finally leads to Type-2 Diabetes (T2D) by an unrevealed mechanism. Initially hIAPP remains at random coil configuration, which periodically convert to β-sheet conformation. From the different studies, it has been observed that if inhibitors could bind to the aggregating peptide and restrict the amyloid formation,it would decrease the propagation of the disease. However, instead ofextensive research to this field, no complete cure have been found until date. In recent studies, several peptide-based inhibitors have been investigated to prevent the aggregation, yet most of them are still suffering with some limitations including, poor binding efficiency, activity at higher doses, poor solubility, proteolyticdegradation etc. To conquer these issues, herein we suggested a design of ‘stapling peptide’ to come into the battle against the fibrillogenesis. Stapled peptides are commonly known to stabilize the -helical conformation and able to take part impressively for protein binding through protein-protein interactions. However, β- sheet stabilisation or destabilisation in aggregating peptides by stapled peptides have not investigated enough. Here, we have explored the modification of a “side chain to tail” stapled peptides via amidation and described their application as modulators of hIAPP self-association and fibrillogenesis. They were also able to disrupt the preformed amyloid of hIAPP into non-toxic species. Moreover, the action of ‘stapling’ effectively enhances the stability towards proteolytic degradation of the peptides in presence of the enzymes. Hence, the stapled peptides can be useful as potent amyloid aggregation inhibitor and open the way for the therapeutic strategy against the amyloid-related disease.
Reference:
1. S. Kalita, S. Kalita, A. Paul, A. Sarkar and B. Mandal, Chem. Sci.,2020, 11, 4171.
National Seminar on Science for Sustainable Development, SSD-2020
PP-17
Control Nucleation and Crystal growth of Drugs in Organogels Himanshu Sharma, TamratYimenuZeleke and BipulSarma*
Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India. *E-Mail: [email protected]
More than 60% of marketed drugs are available in solid formulation and its pharmacokinetic properties of mostly depend on the particle size and shape. The properties of many important drugs fall behind the needed values. Organogels provides an excellent media to control the particle size/shape of drugs to improve these properties. Organogels finds its way in another aspect in drug development process, which involves screening of drug polymorphs before getting regulatory approvals and also vital to safeguard intellectual rights vested upon the drug discovery. Here we report the synthesis of a potential organogel (OG1_Amd) from amide derivative of 4-aminobenzoic acid and benzenetricarbonyl chloride. Solvent screening shows a weak gel formation in alcoholic solvents. The detailed gel screening, gel characterizationsincluding rheology and its application in drug crystallization process is ongoing.
References:
1. Chivers, P. R. and Smith, D. K. Shaping and structuring supramolecular gels. Nature Reviews Materials, 4(7):463-478, 2019. 2. R. G. Weiss, P. Terech (Eds.), Molecular Gels: Materials with Self Assembled Fibrillar Networks, Springer, Dordrecht 2006. 3. Kumar, D. K. and Steed, J. W. Supramolecular gel phase crystallization: orthogonal self- assembly under non-equilibrium conditions. Chemical Society Reviews, 43(7):2080-2088, 2014.
National Seminar on Science for Sustainable Development, SSD-2020
PP-18
Reactivity of 9-anilinoacridine derivatives as potent anticancer agents: A DFRT approach
Pubalee Sarmaha* and Ramesh C. Dekab
aDepartment of Chemistry, Royal Global University Betkuchi, Guwahati-781035, Assam, India bDepartment of Chemical Sciences, Tezpur University Napaam 784028, Assam, India *e-mail: [email protected]
In recent years a large number of 3-(9-acridinylamino)-5-hydroxymethylaniline (AHMA) derivativeswith anticancer activity have been designed and synthesized. Although the DNA-drug sequence-specific binding of AHMA derivatives may be affected by the substituent(s) on the aniline ring, it is still unclear which substituent on the anilino ring of AHMA is the critical element. A good understanding of chemical properties at the molecular level may provide important background of mutagenic and carcinogenic properties.In silico based Quantitative Structure Activity Relationship (QSAR) method is being increasingly applied to generate the possible mechanism of drug target interactions. Density functional theory (DFT) calculations have been proven to be a powerful tool for studying a large variety of problems in the field of biochemistry and computational biology. DFT based QSAR study of some AHMA derivatives to predict anticancer activity and designing of the compounds has been reported.iIn the framework of Density Functional Reactivity Theory (DFRT), we have also reported the reactivity, anticancer activity and property of different systems.ii- viiIn the present study, DFT based reactivity descriptors are calculated to study the reactivity of some AHMAderivativesand their alkyl carbamatesin both gas and solvent phases. Further, QSAR analyses are performed to calculate their anticancer activity.
References:
(1)Chen, J.,Shen, Y., Liao, S., Chen, L., Zheng, K.,Int. J. Quant. Chem. 107, 1468, (2007) (1) Sarmah, P.,J. Mol. Graph.Model. 100,107682, (2020) (1) Sarmah, P., Deka, R.C.,Int. J. Quant. Chem. 108, 1400, (2008) (1) Sarmah, P., Deka, R.C., J. Compt. Aided .Mol. Des.23, 34, (2009) (1)Sarmah, P., Deka, R.C., J. Mol. Model.16, 411, (2010) (1) Barua, N., Sarmah, P., Deka, R.C., Buragohain, A.K.,Chemical Biology & Drug Design79, 553, (2012) (1) Rajkhowa, S., Hussain, I., Hazarika, K.K., Sarmah, P, Deka, R.C., Combinatorial Chemistry & High Throughput Screening16, 590 (2013)
National Seminar on Science for Sustainable Development, SSD-2020
PP-19
A Review on Polymer and Sulphur (S) Chemistry
Rajan Kumar and Raja Shunmugam
Polymer Research Centre (PRC), Centre for Advanced Functional Material (CAFM), Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal E-mail-id: [email protected] The sulphur “S” based polymer plays a vital role to service mankind. The synthetic “S” derived vulcanized/crosslinked polymer was recognized in 19th century by Prof. C. Goodyear (1800- 1860). Today the vulcanized polymers are used for domestic, medical and research purposes. Tyre, hand gloves, utensils, etc represent certain examples. Later in the 20th century Prof. K. B. Sharpless (1941-, Noble prize in Chemistry 2001) categorized hydrothiolation as “Click” reaction. Such hydrothiolation gives advantage in monitoring the elasticity for the material relative to usual uncontrolled “-S-S-” vulcanization. Here we have briefed the importance of the “S” based thiol-ene “Click” polymerization related to engineering optoelectronic viscoelastic gel. The analysis with photonic parameters – Fluorescence Diattenuation (αL/C) and Polarizance (βL/C) revealed unique responses for aggregated specimen (polynuclear aromatic hydrocarbon; PAH) within the hydrothiolated polymer. Such material can be crucial related to photocatalysis, as chemosensor for monitoring wastes, etc.
References
1. G. Odian, Principles of Polymerization, 4th Edition, Wiley-India, New Delhi, 2008 2. P. Theoto, H.-A. Klok, Functional polymers by post-polymerization modification, Wiley-VCH: Germany, 2013. 3. Lowe, A. B. Polymer, 2014, 55, 5517-5549. 4. Kumar, R.; Ray, S. K.; Mukherjee, S.; Saha, S.; Bag, A.; Ghorai, P. K.; Ghosh, N.; Shunmugam. R. Chem. Eur. J., 2019, 25, 13514 – 13522 5. Reineke, S.; Lindner, F.; Schwartz, G.; Seidler, Nico.; Walzer, K.; Lussem, B.; Leo, K. Nature, 459, 234-238. 6. Sekitani, T.; Nakajima, H.; Maeda, H.; Fukushima, T.; Aida, T.; Hata, Kenji.; Someya, T. Nature Materials, 2009, 8, 494-499.
National Seminar on Science for Sustainable Development, SSD-2020
PP-20
Electrical Conductivity Studies of PVA-PVP-Na2SO4Solid Polymer Electrolytesfor Application in Solid State Battery
B. J. Gogoi, A. Murugan*
Department of Chemistry, North Eastern Regional Institute of Science and Technology, Nirjuli, Arunachal Pradesh, India. *Corresponding author. E-mail:[email protected]
Sodium (Na) based rechargeable batteries (SIBs) are now capturing much attention due to its environmental friendly, cost effectiveandnon-toxicnature. Polyvinyl alcohol (PVA) and Polyvinyl pyrrolidone (PVP) polymer blends were prepared and doped with different concentrations of sodium sulphate (Na2SO4)via solution casting method. Depressed semicircles were obtained in the Cole-cole plot. Electrical impedance and conductivity studies of Na2SO4 mixed blend polymer matrices were analysed. The highest conductivity was found to be 2.4 × 10-7 Scm-1at room temperature for 8%
Na2SO4 doped PVA-PVP polymer sample.
Keywords: polymer blend, solution casting method, PVA/PVP, ac impedance, sodium sulphate
National Seminar on Science for Sustainable Development, SSD-2020
Seminar Organizing Committee
(SSD-2020)
President: Dr. Satyendra Nath Barman
Working President: Dr. Sutopa Raichaudhury
Vice President: Dr. Dhruwa Jyoti Choudhury Mr. Dhrubarka Deka Convener: Dr. Bijoy Sankar Goswami Co-Conveners: Mr. Shyamal Kar Dr. Tridip Goswami Dr. Hrishikesh Sarma Dr. Apurba Kalita Mr. Pradyumna Mazumdar Dr. Anupal Gogoi Advisors: Dr. Arup Kumar Misra, Director, ASTEC Dr. Tripti Thakuria, Former Head, Dept. of Chemistry, B Borooah College Dr. Debadutta Borkotoki, Former Director, State Resource Center Dr. Pranab Jyoti Das, Retd. Professor, Dept. of Chemistry, Gauhati University Dr. Abani Kumar Mishra, Retd. Professor, Dept. of Chemistry, Gauhati University Dr. Biplab Mandal, Professor, IIT, Guwahati Dr. Ramesh Ch. Deka, Professor, Tezpur University Dr. Diganta Kumar Das, Registrar, Cotton University Dr. Manjit Bhattacharyya, Associate Professor, Cotton University Dr. Pradip Bhattacharya, Principal, Arya Vidyapith College Treasurer: Dr. Diganta Choudhury
Auditor: Mr. Gagan Deka
National Seminar on Science for Sustainable Development, SSD-2020