Heterocyclic Chemistrychemistry
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Antibiofilm Efficacy of Tea Tree Oil and of Its Main Component Terpinen-4-Ol Against Candida Albicans
ORIGINAL RESEARCH Periodontics Antibiofilm efficacy of tea tree oil and of its main component terpinen-4-ol against Candida albicans Renata Serignoli Abstract: Candida infection is an important cause of morbidity FRANCISCONI(a) and mortality in immunocompromised patients. The increase in its Patricia Milagros Maquera incidence has been associated with resistance to antimicrobial therapy HUACHO(a) and biofilm formation. The aim of this study was to evaluate the Caroline Coradi TONON(a) efficacy of tea tree oil (TTO) and its main component – terpinen-4-ol – Ester Alves Ferreira BORDINI(a) against resistant Candida albicans strains (genotypes A and B) identified by molecular typing and against C. albicans ATCC 90028 and SC 5314 Marília Ferreira CORREIA(a) reference strains in planktonic and biofilm cultures. The minimum Janaína de Cássia Orlandi inhibitory concentration, minimum fungicidal concentration, and SARDI(b) rate of biofilm development were used to evaluate antifungal activity. Denise Madalena Palomari Results were obtained from analysis of the biofilm using the cell (a) SPOLIDORIO proliferation assay 2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H- tetrazolium-5-carboxanilide (XTT) and confocal laser scanning (a) Universidade Estadual Paulista – Unesp, microscopy (CLSM). Terpinen-4-ol and TTO inhibited C. albicans School of Dentistry of Araraquara, Department of Physiology and Pathology, growth. CLSM confirmed that 17.92 mg/mL of TTO and 8.86 mg/mL Araraquara, SP, Brazil of terpinen-4-ol applied for 60 s (rinse simulation) interfered with (b) Universidade Estadual de Campinas – biofilm formation. Hence, this in vitro study revealed that natural Unicamp, School of Dentistry of Piracicaba, substances such as TTO and terpinen-4-ol present promising results Department of Physiological Sciences, for the treatment of oral candidiasis. -
A Facile Approach to Prepare Multiple Heteroatom-Doped Carbon
www.nature.com/scientificreports OPEN A Facile Approach to Prepare Multiple Heteroatom-Doped Carbon Materials from Imine- Received: 17 November 2017 Accepted: 19 February 2018 Linked Porous Organic Polymers Published: xx xx xxxx Juan Yang, Min Xu, Jingyu Wang , Shangbin Jin & Bien Tan In this paper, we proposed a new strategy to prepare multiple heteroatom doped (N, P-doped) porous carbon materials with high surface area of ~1,535 m2 g−1 simply by pyrolysis of imine-linked porous organic polymers (POPs) synthesized via Schif base condensation. The strategy is simple without any post-processing and various heteroatoms could be involved. Scanning electron microscopy, Raman spectra, Nitrogen gas adsorption-desorption, X-ray photoelectron spectroscopy have been used to characterize the morphology, the structure and the composition of the materials. The multiple heteroatom doped porous carbon materials also display high electrocatalytic performance as exampled by the application in oxygen reduction, which showed the catalyst favors 4-electron transfer during the process, along with superior stability and higher tolerance to methanol as compared to the Pt/C. These results indicate the present method is promising for the preparation of multi-heteroatom doped carbon materials in the application of electrocatalysis. Porous organic polymers (POPs) are a type of organic polymers with large surface area, tunable skeleton and high stability1,2. Tey have attracted extensive attentions for broad applications in the felds of gas storage and separations, catalysis and energy storage3–5. Tere are many methodologies reported for the preparation of porous polymers6–10. Among them, Schif base reaction is one of the most versatile ways due to the facile, one-pot, catalyst-free, quantitative synthesis11. -
A New Synthesis of 1-Benzyl-1,2,3,4-Tetrahydroisoquinoline
A NEW SYNTHESIS OF 1-BENZYL-1,2,3,4-TETRAHYDROISOQUINOLINE By L. W. DEADY,*N, H. PIRZADA,*R. D. TOPSOM,"and J. M. BOBBITT~ [Manuscript received 5 March 19731 Abstract The synthesis of N-(2-bromoethy1)-N-(1,2-diphenylethy1)ammoniumbromide and its aluminium chloride catalysed decomposition to 1-benzyl-1,2,3,4-tetrahydro- isoquinoline is described. We have recently reported convenient preparations of tetrahydroquinolinesl (m = 0, n = 3) and tetrahydroisoquinolines2 (m = 1, n = 2) by the cyclization of compounds of type (1). 1-Benzyl-1,2,3,4-tetrahydroisoquinolineis the parent compound of an impor- tant class of alkaloids3 and methods of synthesis of this system are of considerable interest. Normally, the system has been prepared by ring closure between C 1 of the incipient isoquinoline and the aromatic ring, the so-called Bischler-Napieralski rea~tion,~although several new methods have been described and ~ummarized.~In theory, the ring system can be prepared by closure of C4 (as an aldehyde or blocked aldehyde) to the aromatic ring by a variation of the Pomeranz-Fritsch synthe~is,~,~ but there are several difficulties with intramolecular ring closures6 and only one successful synthesis has been reported.' In any case, such a synthesis results in oxygenation at C4 or some type of unsaturation in the isoquinoline ring. In this paper, we report a synthesis which is an extension of our previous work2 and which gives the tetrahydroisoquinoline ring directly in reasonable yield. Deoxybenzoin was used as the starting material in the synthesis of the required intermediate (2). Though the synthesis of (2) involved three steps it was experi- * Organic Chemistry Department, La Trobe University, Bundoora, Vic. -
Organic Chemistry
Wisebridge Learning Systems Organic Chemistry Reaction Mechanisms Pocket-Book WLS www.wisebridgelearning.com © 2006 J S Wetzel LEARNING STRATEGIES CONTENTS ● The key to building intuition is to develop the habit ALKANES of asking how each particular mechanism reflects Thermal Cracking - Pyrolysis . 1 general principles. Look for the concepts behind Combustion . 1 the chemistry to make organic chemistry more co- Free Radical Halogenation. 2 herent and rewarding. ALKENES Electrophilic Addition of HX to Alkenes . 3 ● Acid Catalyzed Hydration of Alkenes . 4 Exothermic reactions tend to follow pathways Electrophilic Addition of Halogens to Alkenes . 5 where like charges can separate or where un- Halohydrin Formation . 6 like charges can come together. When reading Free Radical Addition of HX to Alkenes . 7 organic chemistry mechanisms, keep the elec- Catalytic Hydrogenation of Alkenes. 8 tronegativities of the elements and their valence Oxidation of Alkenes to Vicinal Diols. 9 electron configurations always in your mind. Try Oxidative Cleavage of Alkenes . 10 to nterpret electron movement in terms of energy Ozonolysis of Alkenes . 10 Allylic Halogenation . 11 to make the reactions easier to understand and Oxymercuration-Demercuration . 13 remember. Hydroboration of Alkenes . 14 ALKYNES ● For MCAT preparation, pay special attention to Electrophilic Addition of HX to Alkynes . 15 Hydration of Alkynes. 15 reactions where the product hinges on regio- Free Radical Addition of HX to Alkynes . 16 and stereo-selectivity and reactions involving Electrophilic Halogenation of Alkynes. 16 resonant intermediates, which are special favor- Hydroboration of Alkynes . 17 ites of the test-writers. Catalytic Hydrogenation of Alkynes. 17 Reduction of Alkynes with Alkali Metal/Ammonia . 18 Formation and Use of Acetylide Anion Nucleophiles . -
FIRE-SAFE POLYMERS and POLYMER COMPOSITES September 2004 6
DOT/FAA/AR-04/11 Fire-Safe Polymers and Polymer Office of Aviation Research Washington, D.C. 20591 Composites September 2004 Final Report This document is available to the U.S. public through the National Technical Information Service (NTIS), Springfield, Virginia 22161. U.S. Department of Transportation Federal Aviation Administration NOTICE This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The United States Government assumes no liability for the contents or use thereof. The United States Government does not endorse products or manufacturers. Trade or manufacturer's names appear herein solely because they are considered essential to the objective of this report. This document does not constitute FAA certification policy. Consult your local FAA aircraft certification office as to its use. This report is available at the Federal Aviation Administration William J. Hughes Technical Center’s Full-Text Technical Reports page: actlibrary.act.faa.gov in Adobe Acrobat portable document format (PDF). Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. DOT/FAA/AR-04/11 4. Title and Subtitle 5. Report Date FIRE-SAFE POLYMERS AND POLYMER COMPOSITES September 2004 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Huiqing Zhang 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Polymer Science and Engineering University of Massachusetts Amhurst, MA 01003 11. Contract or Grant No. 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered U.S. Department of Transportation Federal Aviation Administration Office of Aviation Research 14. -
Solvent Effects on Structure and Reaction Mechanism: a Theoretical Study of [2 + 2] Polar Cycloaddition Between Ketene and Imine
J. Phys. Chem. B 1998, 102, 7877-7881 7877 Solvent Effects on Structure and Reaction Mechanism: A Theoretical Study of [2 + 2] Polar Cycloaddition between Ketene and Imine Thanh N. Truong Henry Eyring Center for Theoretical Chemistry, Department of Chemistry, UniVersity of Utah, Salt Lake City, Utah 84112 ReceiVed: March 25, 1998; In Final Form: July 17, 1998 The effects of aqueous solvent on structures and mechanism of the [2 + 2] cycloaddition between ketene and imine were investigated by using correlated MP2 and MP4 levels of ab initio molecular orbital theory in conjunction with the dielectric continuum Generalized Conductor-like Screening Model (GCOSMO) for solvation. We found that reactions in the gas phase and in aqueous solution have very different topology on the free energy surfaces but have similar characteristic motion along the reaction coordinate. First, it involves formation of a planar trans-conformation zwitterionic complex, then a rotation of the two moieties to form the cycloaddition product. Aqueous solvent significantly stabilizes the zwitterionic complex, consequently changing the topology of the free energy surface from a gas-phase single barrier (one-step) process to a double barrier (two-step) one with a stable intermediate. Electrostatic solvent-solute interaction was found to be the dominant factor in lowering the activation energy by 4.5 kcal/mol. The present calculated results are consistent with previous experimental data. Introduction Lim and Jorgensen have also carried out free energy perturbation (FEP) theory simulations with accurate force field that includes + [2 2] cycloaddition reactions are useful synthetic routes to solute polarization effects and found even much larger solvent - formation of four-membered rings. -
Structure-Based Discovery and Synthesis of Potential Transketolase Inhibitors
Supplementary Materials Structure-Based Discovery and Synthesis of Potential Transketolase Inhibitors Jingqian Huo 1,†, Bin Zhao 2,†, Zhe Zhang 1, Jihong Xing 3, Jinlin Zhang 1,*, Jingao Dong 1,3,* and Zhijin Fan 2,4,* 1 College of Plant Protection, Agricultural University of Hebei, Baoding 071001, China; [email protected] (J.H.); [email protected] (Z.Z.) 2 State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, P. R. China; [email protected] 3 College of life science, Agricultural University of Hebei, Baoding 071000, China; [email protected] 4 Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, China * Correspondence: [email protected] (J.Z.); [email protected] (J.D.); [email protected] (Z.F.) † These authors contributed equally to this work. Table of Contents Table S1. The docking affinity of the compounds with transketolase. Figure S1. The binding mode between the small molecules and transketolase. Figure S2. Molecular structure of compound 4b. The appearance, yields, melting points and spectral data of the synthesized compounds. Table S1. The docking affinity of the compounds with transketolase ZINC Affinity ZINC Affinity ZINC Affinity ZINC Affinity ZINC Affinity Compd. (kcal/mol) Compd. (kcal/mol) Compd. (kcal/mol) Compd. (kcal/mol) Compd. (kcal/mol) 12007063 -9.1 05776152 -8.7 12929396 -8.6 67603588 -8.5 41585313 -8.5 19961402 -9 72020240 -8.7 95353804 -8.6 72472311 -8.5 46127235 -8.5 12126699 -9 16283531 -8.7 95353805 -8.6 72472321 -8.5 49169766 -8.5 23186631 -8.8 08654961 -8.6 95381421 -8.6 72472332 -8.5 05175849 -8.5 12130512 -8.8 58191888 -8.6 12130884 -8.6 21941633 -8.5 19706239 -8.5 Molecules 2018, 23, 2116; doi:10.3390/molecules23092116 www.mdpi.com/journal/molecules Molecules 2018, 23, 2116 2 of 11 a b c d e f Figure S1. -
Synthesis of Condensed 1,2,4-Triazolo-Heterocycles
Chemistry SYNTHESIS OF CONDENSED 1,2,4-TRIAZOLO-HETEROCYCLES MOHAMMED A. E. SHABAN ADEL Z. NASR MAMDOUH A. M. TAHA SUMMARY: Cyclization of 2-hydrazino-1, 3-benzothiazole, 2-hydrozinoquioline, 2-hydrazinolepidine, and 2-hydrazino-pyridine with one-carbon cyclizing agents such as triethyl orthoformate, ethyl chlorofor- mate, urea, phenylthiourea, and carbon disulfide gave 3-substituted-1,2,4-triazolo (3,4, -b) 1, 3-benzothia- zoles, 3-substituted-1,2,4-triazolo (4,3-a) quinolines, 3-substituted-1,2,4-triazolo (4,3-a) quinolines, 3-substituted-1,2,4-triazolo (4,3-a) lepidines and 3-substituted-1,2,4-triazolo (4,3-a) pyridines respectively. Reactions with acetic acid and acetic anhydride gave the corresponding acetyl hydrazines which were cyclized to the 3-methyl 1,2,4-triazolo-heterocyles. Ring closure with phenyl isocyanate and phenyl isothio- cyanate, gave the intermediate 4-phenylsemicarbazides and 4-phenylthiosemicarbazides which, upon fusion, afforded the corresponding 3-oxo- and 3-thioxo-1,2,4-triazolo-heterocyles. The 3-oxo-compounds were also obtained when 2-chloroquinoloni or 2-chlorolepidine was fused with semicarbazide hydrochloride. Key Words: Synthesis, amidrazones, triazolo-heterocycles. INTRODUCTION The synthesis and biological activities of condensed In an attempt to prepare 3-methyl-1,2,4-triazolo (3,4-b) 1,2,4-triazolo (3,4-z) heterocyles have recently been 1,3-benzothiazole (5a) by heating 2-hydrazino-1, 3- reviewed (14). Several condendes 1,2,4-triazolo-hetero- benzothiazole (1a) with an excess of acetic acid or acetic cyles exhibit various biological activities such as fungicidal anhydride, 1,1,2-triacetyl-2-(1,3-benzothiazol-2-yl) hyd- (1,9) bactericidal (1,9) analgesic (4,7,10) anxiolytic (8) razine (3a) was obtained. -
Isoxazole—A Basic Aromatic Heterocycle : Synthesis, Reactivity and Biological Activity
International Journal of ChemTech Research CODEN (USA): IJCRGG ISSN: 0974-4290 Vol.8, No.7, pp 297-317, 2015 Isoxazole—A Basic Aromatic Heterocycle : Synthesis, Reactivity And Biological Activity S.S.Rajput1*, Dr. S.N.Patel2, Nilesh B. Jadhav3 1Department of Chemistry, SVS’s Dadasaheb Rawal College Dondaicha 425408, Maharashtra, India. 2Department of Chemistry, S.P.D.M.College, Shirpur 425405, Maharashtra, India. 3Department of Chemistry, S.P.D.M. College, Shirpur425405, Maharashtra, India. Abstract: This review summarizes the synthetic method , reactions and biological application of isoxazoles and summarizes recent development in their derivatives such as chalcone, 5- isoxazole penicillins,shiff base etc.over the last years.The biological activities of isoxazoles is also briefly discussed .Formation of isoxazoles & fused heterocyclic isoxazoles derivatives constitute an interesting class of heterocycles which have diverse biological activities. Keywords: Isoxazoles, biological activity, 5-isoxazole penicillin. 1. Introduction Substituted Isoxazoles are important compounds of many drugs and drug candidates. It is one of the most fundamental objectives of organic and medicinal chemistry is the design and synthesis of molecules having value human therapeutic agents. The diversity of biological activities and pharmaceutical uses have been attributed to them, such as isoxazole is a part of many active molecule possessing activities such as Anti- tubercular[1], Analgesic[2], Antipyretic[2], Anti-inflammatory[2][3], Antiplatelet[4], Anti-HIV[4], Antagonist activity[4], CNS depressant[5], Antifungal[6][7], Antibacterial[6][7][8], Anti-oxidant[7], Anticancer[9][10] . The Substituted isoxazole moiety 1 appears as an interesting precursor of many biologically active of the above class compounds. -
Antifungal Agents in Agriculture: Friends and Foes of Public Health
biomolecules Review Antifungal Agents in Agriculture: Friends and Foes of Public Health Veronica Soares Brauer 1, Caroline Patini Rezende 1, Andre Moreira Pessoni 1, Renato Graciano De Paula 2 , Kanchugarakoppal S. Rangappa 3, Siddaiah Chandra Nayaka 4, Vijai Kumar Gupta 5,* and Fausto Almeida 1,* 1 Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP 14049-900, Brazil; [email protected] (V.S.B.); [email protected] (C.P.R.); [email protected] (A.M.P.) 2 Department of Physiological Sciences, Health Sciences Centre, Federal University of Espirito Santo, Vitoria, ES 29047-105, Brazil; [email protected] 3 Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570006, India; [email protected] 4 Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India; [email protected] 5 Department of Chemistry and Biotechnology, ERA Chair of Green Chemistry, Tallinn University of Technology, 12618 Tallinn, Estonia * Correspondence: [email protected] (V.K.G.); [email protected] (F.A.) Received: 7 July 2019; Accepted: 19 September 2019; Published: 23 September 2019 Abstract: Fungal diseases have been underestimated worldwide but constitute a substantial threat to several plant and animal species as well as to public health. The increase in the global population has entailed an increase in the demand for agriculture in recent decades. Accordingly, there has been worldwide pressure to find means to improve the quality and productivity of agricultural crops. Antifungal agents have been widely used as an alternative for managing fungal diseases affecting several crops. However, the unregulated use of antifungals can jeopardize public health. -
Electrooxidation Enables Highly Regioselective Dearomative Annulation of Indole and Benzofuran Derivatives
ARTICLE https://doi.org/10.1038/s41467-019-13829-4 OPEN Electrooxidation enables highly regioselective dearomative annulation of indole and benzofuran derivatives Kun Liu1, Wenxu Song1, Yuqi Deng1, Huiyue Yang1, Chunlan Song1, Takfaoui Abdelilah1, Shengchun Wang 1, Hengjiang Cong 1, Shan Tang1 & Aiwen Lei1* 1234567890():,; The dearomatization of arenes represents a powerful synthetic methodology to provide three-dimensional chemicals of high added value. Here we report a general and practical protocol for regioselective dearomative annulation of indole and benzofuran derivatives in an electrochemical way. Under undivided electrolytic conditions, a series of highly functio- nalized five to eight-membered heterocycle-2,3-fused indolines and dihydrobenzofurans, which are typically unattainable under thermal conditions, can be successfully accessed in high yield with excellent regio- and stereo-selectivity. This transformation can also tolerate a wide range of functional groups and achieve good efficiency in large-scale synthesis under oxidant-free conditions. In addition, cyclic voltammetry, electron paramagnetic resonance (EPR) and kinetic studies indicate that the dehydrogenative dearomatization annulations arise from the anodic oxidation of indole into indole radical cation, and this process is the rate- determining step. 1 College of Chemistry and Molecular Sciences, Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, P. R. China. *email: aiwenlei@whu. edu.cn NATURE COMMUNICATIONS | (2020) 11:3 | https://doi.org/10.1038/s41467-019-13829-4 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | https://doi.org/10.1038/s41467-019-13829-4 reaking the aromatic systems of electron-rich arenes or fused indolines (Fig. 1a)39–44. Therefore, it is highly appealing to heteroarenes provides three-dimensional chemicals of high develop efficient approaches to allow for their preparation. -
Benzofuran Synthesis Through Iodocyclization Reactions: Recent Advances
MOJ Bioorganic & Organic Chemistry Mini Review Open Access Benzofuran synthesis through iodocyclization reactions: recent advances Abstract Volume 1 Issue 7 - 2017 Recent advancements (2014-17) in the benzofuran synthesis through iodocyclization Saurabh Mehta have been summarized. The successful use of various iodinating agents, bases, additives Department of Applied Chemistry, Delhi Technological etc. make iodocyclization a versatile and efficient methodology. The methodology has University, India been applied for the synthesis of more complex benzofuran derivatives, and may open interesting avenues in the area of heterocyclic chemistry (Figure 1). Correspondence: Saurabh Mehta, Department of Applied O-LG Chemistry, Delhi Technological University, Bawana Road, Delhi, + O R1 I 1 2 110042 India, Tel +9188 0066 5868, R R Email [email protected], [email protected] R2 I Received: December 17, 2017 | Published: December 29, 2017 LG = H, Me or other Protecting group 1 R = H, Me, OMe, I, CO2Me, etc. R2 = H, aryl, alkyl, alkenyl, etc. Figure 1 Keywords: annulations, alkyne, benzofuran, iodocyclization, heterocycle Introduction derivatives were obtained in high yields (84%−100%) under mild conditions. The authors demonstrated that the choice of bis(2,4,6- Benzo[b]furan is a privileged heterocyclic scaffold. Several collidine)iodonium hexafluorophosphate [I(coll)2PF6] as the compounds containing this scaffold have interesting biological iodinating agent was necessary for the success of the reaction. Also, 1 activities, such as anti-cancer, anti-viral, anti-inflammatory, etc. Few the ethoxyethyl ether group acted as a protecting group as well as a 2 derivatives are even used as commercial drugs, such as Amiodarone, good leaving group.