DOCSLIB.ORG

Université D'orléans

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Université D'orléans Universidade de Lisboa Faculdade de Ciências Departamento de Química e Bioquímica Université d’Orléans Institut de Chimie Organique et Analytique Carbohydrate-based 1,3-oxazoline-2-thiones as original bioactive structures. Synthesis and reactivity. Sandrina Isabel Ribeiro Martins da Silva Supervised by: Amélia Pilar Rauter (Professora Associada com Agregação do Departamento de Química e Bioquímica da Faculdade de Ciências da Universidade de Lisboa) Patrick Rollin (Professeur Classe Exceptionnelle 1 de l’Université d’Orléans) Jorge Guerra Justino (Professor Coordenador com Agregação da Escola Superior Agrária do Instituto Politécnico de Santarém) Doutoramento em Química (Química Orgânica) 2008 II Wonder is the beginning of all science Aristotle III IV Acknowledgements First of all, I would like to express my deep sense of gratitude to my supervisors, Prof. Amélia Pilar Rauter and Prof. Patrick Rollin, for the opportunity they gave me to develop this interesting subject of research. Their excellent guidance, inspiration, encouragement and support were crucial for the success of this project. I want to express my grateful thanks to Prof. Jorge Justino for his high implication and fruitful discussions about antimicrobial activity. The motivation he gave me during this project was also very important to me. I also would like to thank to Fundação para a Ciência e Tecnologia for the PhD grant SFRH/BD/16937/2004. In a special way, I want to thank Dr. Arnaud Tatibouët, for his availability, good advices, patience, sympathy and constant support during this project. All over these years and each day, many persons shared with me the laboratory and life, being decisive for the development of this project in a good environment. Among them, I want to thank particularly Abdel, AnaCat, Charlotte, Deimas, Sarona, Balla, Laury, Claudita, Yoyo, Sebastien, Ilona, Julie, Vanessa, Anthony, Andreia, Filipa, Elise, Mathilde, Monika, Alexis, Eddy, Nicholas Leconte, Stephane, petit et grand Mathiew, Jamal, Ahmed, Catherine, Nicholas Weisse, Aude, Virginie, Rajaâ, Aziz, Laurent, Ugo, Aurelien, Florent, Damien, Pamela, Aurélie, Mathéo, Fred, Joana, Zack, Fabienne, Jerôme, Mimi, Helène, Veronique, Christelle Pillard, Christelle Lopin, Franck, Sylvan, Marie Madeleine, Jean-Marie, Jean-Yves Coadou, Nathalie, Susana, Nuno, Ana Vicente, Filipa, João, Caio, Ana N., Ana C. and Bernard. I want to express my grateful thanks to Prof. Carmen Ortiz Mellet, for the availability to test my compounds against glycosidase inhibitors and for helpful discussions. I also want to thank Filipa Vinagre for the tests of antimicrobial activity. My dear friends, Rita, Susana, Mauro, Eliana, Nuno, Carlos e André, I want to thank them very much for their support during this PhD. Also, and in a special way, I want to thank Rui for all love and comprehension he demonstrated during these years, especially when I was in France. At last, but not least, I could not finish without thanking my parents Fátima e Jorge and my sister Fátima. Quero agradecer-vos do fundo do coração todo o apoio incondicional que me têm dado desde que comecei esta etapa da minha vida e todos os sacrifícios que têm feito ao longo dos meus estudos. A vossa presença e motivação constantes são a base da força que sinto cada dia, para enfrentar algumas dificuldades e lutar pelos meus objectivos. São a melhor família do mundo e sou muito feliz por pertencer a ela! V VI To my parents To my sister To my grandparents VII VIII Abstract The resistance of microorganisms to antibiotics is, in our days, one of the biggest problems in terms of public health. The research for new artificial and natural families of compounds throws us towards innovative methodologies leading to novel antibiotics. In the present work, we are invited to dive in the “new world” of 1,3- oxazoline-2-thiones (OXTs, structure-type i) regarding their synthesis, reactivity and biological activity. In fact, this heterocycle is a simple synthon readily obtained by condensation of thiocyanic acid with an α-hydroxycarbonyl species. When compared to their non-aromatic counterpart 1,3-oxazolidine-2-thiones (OZTs, structure-type ii ), this family of compounds is still unexplored. S S HN O HN O R R' R R' i ii When the heterocycle is anchored on a carbohydrate template (i.e. a more complex chiral α-hydroxycarbonyl moiety), original structures are expected such as OZTs fused to five- or six-membered rings (structures-type iii , iv , v and vi) and OXTs C-C linked to sugars (structure-type vii) , with a broad potential in organic chemistry and bioorganic applications. RO RO O RO X OR O O HO O O O RO HO S HN O S Y OR O HN OR N OH S H OH OR NH O X= O, Y= NH S S X= NH, Y= O iii iv v vi vii IX The work developed in this PhD is presented in five chapters. In the first one, the formation and reactivity of sulfur and nitrogen centres of a simple OXT were investigated. In the second one, we have developed the synthesis of thionocarbamates fused to carbohydrate templates, as well as the study of the reactivity of the sulfur center in such bicyclic systems, leading to the formation of new carbohydrate-fused oxazolidinones (OZOs). The third chapter is dedicated to the synthesis and reactivity of C-C linked OXTs to a sugar moiety. Moreover, from the exploitation of the sulfur and nitrogen centers, different families of compounds were raised, such as pseudo-C-iminosugars and oxazoles. In the fourth chapter, we have explored the use of thioxo compounds as electrophiles in Pd-assisted cross-coupling methods, such as Suzuki and Stille reactions. A new modified Sonogashira cross-coupling reaction, in which copper (I) is used in catalytic amount, was developed and its feasibility was proven for a variety of substrates. In the last chapter, we focused on the biological potential of the new molecules. We have targeted a broad spectrum of antimicrobial activity for some OXTs and OZTs, to which was added a screening of glycosidases inhibition for the pseudo-C-iminosugars. X Resumo A resistência dos microorganismos aos antibióticos é um dos maiores problemas nos dias de hoje, em termos de saúde pública. É pois urgente desenvolver novas formas de combate a este problema, que nos orientem para a investigação de novos antibióticos naturais e artificiais. No âmbito deste projecto de investigação somos convidados a mergulhar no “novo mundo” das 1,3-oxazolina-2-tionas (OXTs), estudando a sua síntese, reactividade e actividade biológica. Este heterociclo aromático, de estrutura i, é um composto facilmente obtido através da condensação do ácido tiociânico com uma unidade estrutural α-hidroxicarbonilo e, ao contrário dos compostos com o anel não aromático 1,3-oxazolidina-2-tiona (OZT, estrutura ii) , não está bem estudado, sendo a literatura bastante escassa no que respeita a esta família de heterociclos. S S HN O HN O R R' R R' i ii A ligação de OXTs a hidratos de carbono modelo, que possuem a unidade α- hidroxicarbonilo, conduz à formação de estruturas originais, como por exemplo derivados de OZT fusionada a açúcares de cinco e seis membros (estruturas de tipo iii , iv , v e vi) , bem como pseudo-C-nucleósidos de tipo vii , com enorme potencial em química orgânica e em aplicações bioorgânicas. RO RO O RO X OR O O HO O O O RO HO S HN O S Y OR O HN OR N OH S H OH OR NH O X= O, Y= NH S S X= NH, Y= O iii iv v vi vii O projecto desenvolvido neste doutoramento é apresentado em cinco capítulos. XI Numa primeira parte do projecto, foram investigadas as condições ideais para a síntese de OXTs, tendo sido demonstrado que a sua formação é possível com uma vasta gama de solventes e ácidos, sendo o aspecto mais importante a escolha do par solvente/ácido para efectuar a reacção. Esta primeira parte foi também dirigida para o estudo de reactividade padrão do enxofre e do azoto, envolvendo processos de alquilação, acilação, sulfonilação e adições de tipo Michael. Durante todos estes processos, verificou-se que a aromaticidade do anel assume um papel muito importante na reactividade do enxofre e, em especial, na do azoto, ficando demonstrado que a reactividade de OXTs é completamente diferente da descrita na literatura referente às OZTs. Numa segunda parte do trabalho, os nossos esforços concentraram-se na síntese de tionocarbamatos fusionados a hidratos de carbono modelo, com estruturas de tipo iii , iv, v e vi . Assim, envolvendo reacções de protecção, desprotecção e oxidação, foi introduzida a unidade α-hidroxicarbonilo em açúcares a partir dos compostos 1,2-isopropilideno-α-D-xylofuranose, α-D-glucopiranósido de metilo e β- D-glucopiranósido de metilo. Estas α-hidroxicetonas complexas foram utilizadas como precursores das moléculas-alvo, as OXTs fusionadas aos acúcares. No entanto, a condensação com o ácido tiociânico conduziu à formação de OXTs fusionadas hidratadas, que revelaram uma maior estabilidade em relação às correspondentes OXTs fusionadas. Muito importante é também o facto de a estereoquímica destas OXTs fusionadas hidratadas depender absolutamente da posição e da orientação do grupo hidroxilo envolvido na reacção – uma relação cis foi sempre verificada. Quando a condensação com o ácido tiociânico é realizada entre as posições 2 e 3 do hidrato de carbono, a configuração da posição anomérica mostra ter influência decisiva na formação das OXTs hidratadas – para os α-glicósidos, em que se observa a relação 1,2-cis , a reacção de condensação mostra-se ineficaz. No entanto, quando a condensação é efectuada nos β-glicósidos, a mesma decorre sem problemas e com bons rendimentos. XII Após protecção do enxofre através de uma reacção de S-benzilação e tratamento com ácido tríflico foi possível a desidratação dos compostos de tipo iii, conduzindo à formação das correspondentes OXTs fusionadas.
Load more

Recommended publications
  • Thiirane-Terminated Polysulfide Polymers Thiiran-Terminierte Polysulfidpolymere Polymères Polysulfures À Terminaison Thiirane
    (19) & (11) EP 2 121 807 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.: of the grant of the patent: C08G 75/00 (2006.01) 26.05.2010 Bulletin 2010/21 (86) International application number: (21) Application number: 08707985.1 PCT/EP2008/050540 (22) Date of filing: 18.01.2008 (87) International publication number: WO 2008/090086 (31.07.2008 Gazette 2008/31) (54) THIIRANE-TERMINATED POLYSULFIDE POLYMERS THIIRAN-TERMINIERTE POLYSULFIDPOLYMERE POLYMÈRES POLYSULFURES À TERMINAISON THIIRANE (84) Designated Contracting States: • KOTTNER, Nils AT BE BG CH CY CZ DE DK EE ES FI FR GB GR D-78628 Rottweil (DE) HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT • ZEITLER, Michael RO SE SI SK TR D-53347 Alfter (DE) (30) Priority: 23.01.2007 EP 07101024 (74) Representative: Schalkwijk, Pieter Cornelis et al 02.02.2007 US 899273 P Akzo Nobel N.V. Intellectual Property Department (43) Date of publication of application: P.O. Box 9300 25.11.2009 Bulletin 2009/48 6800 SB Arnhem (NL) (73) Proprietor: Akzo Nobel N.V. (56) References cited: 6824 BM Arnhem (NL) WO-A-03/076487 WO-A1-2004/099283 JP-A- 2004 062 057 US-A- 5 173 549 (72) Inventors: • WITZEL, Silke D-42103 Wuppertal (DE) Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations.
    [Show full text]
  • Synthesis and Inclusion Studies of Stable
    The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. The thesis is to be used for private study or non- commercial research purposes only. Cape Published by the University ofof Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University SYNTHESIS AND INCLUSION STUDIES OF STABLE ALLICIN MIMICS AS NOVEL ANTIMICROBIAL AGENTS BY Nashia StellenboomTown Cape Thesis Presentedof for the Degree of DOCTOR OF PHILOSOPHY In the Department of Chemistry UniversityUNIVERSITY OF CAPE TOWN April 2008 Supervisors Professor Roger Hunter and Professor Mino R. Caira Table of Contents ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Chapter 1 : Introduction 1 1.1 Overview of Garlic 1 1.2 Allicin 2 1.3 Thiosulfinates 12 1.4 The Disulfide Bond 14 1.5 Review of Unsymmetrical Disulfide Synthesis 22 1.6 Cyclodextrins 55 1.7 Aims and Objectives 63 Chapter 2 : Unsymmetrical Disulfides 64 2.1 Unsymmetrical Disulfide Synthesis 64 Chapter 3 : S-Alkyl Arylthiosulfinates 109 Town 3.1 Overview 109 3.2 The Chemistry of Oxidation of Unsymmetrical Disulfides 113 3.3 Electron-Rich systems 118 3.4 Electron-Deficient systems Cape 120 3.5 π-Deficient Heteroaromatic System 121 3.6 Stability Tests of S-alkyl arylthiosulfinatesof 128 3.7 S-p-Methoxyphenyl Alkylthiosulfinates 130 Chapter 4 : Cyclodextrin Inclusion 142 4.1 Overview 142 4.2 Experimental, Methods and Materials 142 4.3 Results andUniversity Discussion 146 4.4 Conclusion 161 Chapter 5 : Summary and Conclusion 162 Chapter 6 : Experimental 163 6.1 General Procedure 163 6.2 Synthesis and Purification of Disulfides 164 6.3 Compounds 166 References 193 Abstract ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ABSTRACT Allicin, a known constituent of garlic, is a potent but unstable antimicrobial agent.
    [Show full text]
  • The Chemistry of Heterocycles Structure, Reactions, Syntheses
    The Chemistry of Heterocycles Structure, Reactions, Syntheses, and Applications Mohammad Jafarzadeh Faculty of Chemistry, Razi University The Chemistry of Heterocycles, (Second Edition). By Theophil Eicher and Siegfried Hauptmann, Wiley-VCH Veriag GmbH, 2003 1 24 3 Three-Membered Heterocycles 3.2 Thiirane 24 3 Three-Membered Heterocycles 3.2 Thiirane Thiiranes are also known as episulfides. As a result of the greater atomic radius of the S-atom, the three atoms form an acute-angled triangle (see Fig. 3.2). [A] Thiiranes are also known as episulfides. As a result of the greater atomic radius of the S-atom, the 3.2 Thiirane three atoms form an acute-angled triangle. Fig. 3.2 Structure of thiirane (bond lengths in pm, bond angles in degrees) The thermochemically determined strainThenthalpye thermochemicallof thiiraney determineof 83 kJd molstrai-1n isenthalplessythan of thiiranthateof ofoxirane 83 kJ mo. H is less than that of oxirane. The ionization potential amounts to 9.05TheV,e ionizatiothe dipolen potentiamomentl amountto 1.66s toD 9.0. Both5 eVvalues, the dipolaree belowmomenthoset to 1.66 D. Both values are below Thiiranes are also known aofsoxirane episulfides. The chemical. Ashiftss a resulin the NMRt thosofspectrae thof oxiranee greateare. �ThH e= chemica2r. 27atomi, �l Cshift= 18sc i .n1radiu .the NMRs spectrof ath are S ^S-atom = 2.27, Sc ,=18.1. the three atoms form an acute-angled triangle (see Fig. 3.2)Th.e properties of the thiiranes are primarily due to ring strain. In spite of the smaller strain en- [B] The properties of the thiiranes are primarilythalpydue, tothiiranringestrain is thermall.
    [Show full text]
  • Recent Synthesis of Thietanes
    Recent synthesis of thietanes Jiaxi Xu Review Open Access Address: Beilstein J. Org. Chem. 2020, 16, 1357–1410. State Key Laboratory of Chemical Resource Engineering, Department doi:10.3762/bjoc.16.116 of Organic Chemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China Received: 29 March 2020 Accepted: 26 May 2020 Email: Published: 22 June 2020 Jiaxi Xu - [email protected] Associate Editor: B. Nay Keywords: © 2020 Xu; licensee Beilstein-Institut. cycloaddition; cyclization; ring contraction; ring expansion; thietane; License and terms: see end of document. thiotherification Abstract Thietanes are important aliphatic four-membered thiaheterocycles that are found in the pharmaceutical core and structural motifs of some biological compounds. They are also useful intermediates in organic synthesis. Various synthetic methods of thietanes have been developed, including inter- and intramolecular nucleophilic thioetherifications, photochemical [2 + 2] cycloadditions, ring expansions and contractions, nucleophilic cyclizations, and some miscellaneous methods. The recently developed methods provide some new strategies for the efficient preparation of thietanes and their derivatives. This review focuses on the synthetic methods to construct thietane backbones developed during 1966 to 2019. Review 1. Introduction Thietanes are a class of important aliphatic four-membered thia- acyclic and heterocyclic compounds [10,11]. Several synthetic heterocycles. Some simple alkyl and dialkyl thietanes
    [Show full text]
  • [Thesis Title Goes Here]
    SWITCHABLE SOLVENTS FOR NOVEL CHEMICAL PROCESSING A Thesis Presented to The Academic Faculty by Joshua David Grilly In Partial Fulfillment of the Requirements for the Degree Master’s of Science in the School of Chemical and Biomolecular Engineering Georgia Institute of Technology December, 2005 SWITCHABLE SOLVENTS FOR NOVEL CHEMICAL PROCESSING Approved by: Dr. Charles Eckert, Advisor School of Chemical and Biomolecular Engineering Georgia Institute of Technology Dr. Charles Liotta, Co-Advisor School of Chemical and Biomolecular Engineering Georgia Institute of Technology Dr. Rigoberto Hernandez School of Chemistry Georgia Institute of Technology Date Approved: August 11, 2005 ACKNOWLEDGEMENTS I would like to start by thanking my advisors, Dr. Charles Eckert and Dr. Charles Liotta and my other committee member, Dr. Rigoberto Hernandez. I would have never gotten to this point without Dr. Eckert’s constant wisdom and guidance. His constant question of, “What do we win if we win” always helped me to see the big picture. Dr. Liotta’s ever-present humor and knowledge of all things chemistry have greatly enhanced my experience here on both a personal and professional level. I would like to thank Deborah Babykin, who always had time to help me with whatever I needed. I would like to thank all of the current and former members of the Eckert-Liotta group. They have made my time here much more enjoyable. Specifically, I would like to thank Josh Brown, who could fix anything; Jason Hallett, who always seemed to know what was going on in the lab and on the baseball diamond; Josh Aronson and Colin Thomas for their invaluable assistance on these projects, and Laura Nunez for all of her hard work.
    [Show full text]
  • An Improved Method for the Conversion of Oxiranes to Thiiranes and the Discrimination of Their Base Peaks in EI-MS
    General Papers ARKIVOC 2012 (viii) 157-168 An improved method for the conversion of oxiranes to thiiranes and the discrimination of their base peaks in EI-MS a b c b b, Hsing-Ming Chen, Po-Yuan Chen, Chih-Feng Wang, Jui-Chi Tsai, and Eng-Chi Wang * aDepartment of Nutrition and Health Science, Fooyin University, Kaohsiung 831, Taiwan bDepartment of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan cDepartment of Materials Science & Engineering, I-Shou University, Kaohsiung 82445, Taiwan E-mail: [email protected] DOI: http://dx.doi.org/10.3998/ark.5550190.0013.815 Abstract An efficient method for the conversion of oxiranes to thiiranes by treatment with excess ammonium thiocyanate in aqueous media under reflux or by microwave irradiation is reported. Keywords: Epoxides, ammonium thiocyanate, thiiranes, base peak, EI-MS Introduction Thiiranes are valuable synthetic building blocks with industrial potential for the preparation of polymers,1 liquid crystals,2 adhesives,3 as many others.4 In addition, thiirane is an essential heterocyclic core of various compounds with biological activity including selective gelatinase 5 6 7 inhibitors, selective A1 adenosine receptor agonists, potential topoisomerase I inhibitors, estrogen synthetase inhibitor8. As a result chemists have made efforts to create an efficient and environmentally benign method for the synthesis of thiiranes. Strategies for the preparation of thiiranes include (1) reaction of alkenes with various reagents including dichlorodisulfides,9 and iodothiocyanate,10 (2) reaction of ketones with a sulfuryl lithium,11 (3) reduction of 1- (benzthiazol-2-yl-sulfanyl)-2-alkanones with sodium hydride,12 (4) reaction of epoxides with ammonium thiocyanate,13 or potassium thiocyanate;14 (5) conversion of epoxides with thiourea,15 as well as other methods.16 Among the methods described above, preparation of thiiranes from epoxides, by reaction ammonium thiocyanate with various catalysts and solvents, has been intensively studied and summarized in Table 1.
    [Show full text]
  • The Preparation and Reactions of 3,3-Disubstituted Thietanes and Their Derivatives
    University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 1975 THE PREPARATION AND REACTIONS OF 3,3-DISUBSTITUTED THIETANES AND THEIR DERIVATIVES MARIS BUZA Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation BUZA, MARIS, "THE PREPARATION AND REACTIONS OF 3,3-DISUBSTITUTED THIETANES AND THEIR DERIVATIVES" (1975). Doctoral Dissertations. 1089. https://scholars.unh.edu/dissertation/1089 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. INFORMATION TO USERS This material was produced from a microfilm copy of the original document. While the most advanced technological means to photograph and reproduce this document have been used, the quality is heavily dependent upon the quality of the original submitted. The following explanation of techniques is provided to help you understand markings or patterns which may appear on this reproduction. 1. The sign or "target” for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting thru an image and duplicating adjacent pages to insure you complete continuity. 2. When an image on the film is obliterated with a large round black mark, it is an indication that the photographer suspected that the copy may have moved during exposure and thus cause a blurred image.
    [Show full text]
  • Some Chemicals Used As Solvents and in Polymer Manufacture
    SOME CHEMICALS USED AS SOLVENTS AND IN POLYMER MANUFACTURE AND IN POLYMER SOME CHEMICALS USED AS SOLVENTS SOME CHEMICALS USED AS SOLVENTS AND IN POLYMER MANUFACTURE VOLUME 110 IARC MONOGRAPHS ON THE EVALUATION OF CARCINOGENIC RISKS TO HUMANS SOME CHEMICALS USED AS SOLVENTS AND IN POLYMER MANUFACTURE VOLUME 110 This publication represents the views and expert opinions of an IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, which met in Lyon, 3–10 June 2014 LYON, FRANCE - 2017 IARC MONOGRAPHS ON THE EVALUATION OF CARCINOGENIC RISKS TO HUMANS IARC MONOGRAPHS In 1969, the International Agency for Research on Cancer (IARC) initiated a programme on the evaluation of the carcinogenic risk of chemicals to humans involving the production of critically evaluated monographs on individual chemicals. The programme was subsequently expanded to include evaluations of carcinogenic risks associated with exposures to complex mixtures, lifestyle factors and biological and physical agents, as well as those in specific occupations. The objective of the programme is to elaborate and publish in the form of monographs critical reviews of data on carcinogenicity for agents to which humans are known to be exposed and on specific exposure situations; to evaluate these data in terms of human risk with the help of international working groups of experts in carcinogenesis and related fields; and to indicate where additional research efforts are needed. The lists of IARC evaluations are regularly updated and are available on the Internet at http:// monographs.iarc.fr/. This programme has been supported since 1982 by Cooperative Agreement U01 CA33193 with the United States National Cancer Institute, Department of Health and Human Services.
    [Show full text]
  • Method for Producing Vicinal Dithiol Verfahren Zur Herstellung Von Vicinalen Dithiolen Procédé Pour La Préparation De Thiols Vicinaux
    (19) & (11) EP 1 564 207 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.: of the grant of the patent: C07C 319/02 (2006.01) C07C 327/22 (2006.01) 02.06.2010 Bulletin 2010/22 (21) Application number: 05101082.5 (22) Date of filing: 14.02.2005 (54) Method for producing vicinal dithiol Verfahren zur Herstellung von vicinalen Dithiolen Procédé pour la préparation de thiols vicinaux (84) Designated Contracting States: (74) Representative: Gille Hrabal Struck Neidlein Prop DE FR GB Roos Patentanwälte (30) Priority: 17.02.2004 JP 2004040619 Brucknerstrasse 20 40593 Düsseldorf (DE) (43) Date of publication of application: 17.08.2005 Bulletin 2005/33 (56) References cited: US-A1- 2003 195 270 (73) Proprietor: MITSUBISHI GAS CHEMICAL COMPANY, INC. • DATABASE WPI Section Ch, Week 200441 Chiyoda-ku, Derwent Publications Ltd., London, GB; Class Tokyo (JP) A41, AN 2004-433442 XP002331198 & JP 2004 107278A (MITSUBISHI GAS CHEM CO INC) 8 April (72) Inventors: 2004 (2004-04-08) • KONDO, Mitsuteru Tokyo (JP) Remarks: • TAKEUCHI, Motoharu Thefile contains technical information submitted after Tokyo (JP) the application was filed and not included in this • JOHNO, Masahiro specification Tokyo (JP) • ISHII, Kenji Tokyo (JP) Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been paid. (Art.
    [Show full text]
  • Fariba Heidarizadeh 2.Pmd
    ORIENTAL JOURNAL OF CHEMISTRY ISSN: 0970-020 X CODEN: OJCHEG An International Open Free Access, Peer Reviewed Research Journal 2011, Vol. 27, No. (4): Pg. 1531-1553 Est. 1984 www.orientjchem.org Some Versatile and Efficient Methods for the Regioselective Ring Opening of Epoxides to Corresponding β-Hydroxy Thiocyanates FARIBA HEIDARIZADEH¹ and SOMAYEH ELAHI² ¹Department of Chemistry, Faculty of Science, Shahid Chamran University, Ahvaz (Iran). ²Abadan Branch, Islamic Azad University, Abadan (Iran). *Corresponding author: E-mail: [email protected] (Received: April 12, 2011; Accepted: June 04, 2011) ABSTRACT In this review, was reported some methods for the preparation of â-hydroxy thiocyanates, which are considered as an important class of compounds often used as key intermediates in agricultural and pharmaceutical chemistry. Key words: Regioselectivity, Ring opening, Thiocyanohydrin, Epoxide, β-Hydroxythiocyanate, Solid phase, Liquid phase. INTRODUCTION electrophiles, nucleophiles, acids, and bases3-4. The ring opening of epoxides with different β-hydroxy thiocyanates play an important nucleophiles is an attractive subject in organic role in the realm of organic chemistry, such as transformations5. biological, pharmaceutical and agricultural chemistry1. In the recent decade, these compounds Between these nucleophiles, the reaction were prepared by the reaction of different epoxides of thiocyanate ion with epoxides, in the absence or with NH4SCN in the presence of various catalysts in the presence of catalyst is a widely studied and
    [Show full text]
  • Chemical Characterization of 465 Known Or Suspected Carcinogens and Their Correlation with Mutagenic Activity in the Salmonella Typhimurium System1
    (CANCER RESEARCH 39, 3289-331 8, september 1979] 0008-5472/79/0039-0000$02.OO Chemical Characterization of 465 Known or Suspected Carcinogens and Their Correlation with Mutagenic Activity in the Salmonella typhimurium System1 Stephen J. Rinkus2 and Marvin S. Legator Department of Preventive Medicine and Community Health, Division of Environmental Toxicology, University of Texas Medical Branch, Galveston, Texas 77550 ABSTRACT studieson groupsof carcinogenicand noncarcinogenicchem icals. Actually, the reported correlations between carcinogenic Since chemicals exhibiting mutagenic activity pose a poten ity and mutagenicity in Salmonella range from 63 to 92%. With tial hazard to their users, there is increasing acceptance of the exception of a brief comment by Odashima (172) on struc mutagenicity testing as an integral part of a premarketing ture-activity relationships apparent among false negatives and toxicological evaluation of chemicals. In vitro testing has gained false positives, there has been little indication that certain much notoriety as a quick and relatively inexpensive means to chemical categories of carcinogens are not well detected in assess the mutagenic potential of chemicals. However, the Salmonella. That the higher correlations do not necessarily innovative use of microsomes to simulate metabolism has not translateinto a correspondinglyhigh ability to detect carcino changed the fact that in vitro activation cannot duplicate faith gensfromamonganygroupof chemicalsisillustratedinTables fully the metabolism that occurs in vivo. This shortcoming will 1 and 2. Presented are the Salmonella testing results of 12 express itself by the production of false negatives and possibly pesticides judged positive for tumor induction by an expert false positives during mutagenicity screening. This assertion is panel of scientists reviewing the available studies (62).
    [Show full text]
  • Compound Index in This Index the Molecular Structures Are Listed in Alphabetical Order of the Sum Formulae in Hill System
    Compound Index In this index the molecular structures are listed in alphabetical order of the sum formulae in Hill system. Therefore, the molecular structures of the inorganic molecules, which are presented in Chapter 2, are given in the beginning and in the end of the compound index. In between there is a block of 818 compounds containing one or more carbon atoms (Chapters 3 to 10). Entry Molecular MGD Chemical name No. formula RN 1 AgArI 537270 Silver iodide – argon (1/1) 2 AgClH2 405223 Chloro(dihydrogen-H,H)silver 3 AgClH2O 215060 Silver chloride – water (1/1) 4 AgClH2S 212935 Silver chloride – hydrogen sulfide (1/1) 5 AgClH3N 214142 Silver chloride – ammonia (1/1) 6 AgFH2O 216055 Silver fluoride – water (1/1) 7 AgHS 349976 Silver hydrogen sulfide 8 AgH2 216264 Silver (1+)ion – dihydrogen (1/1) 9 AgH2IO 549396 Silver iodide – water (1/1) 10 AgH2IS 333978 Silver iodide – hydrogen sulfide (1/1) 11 AgH3IN 478020 Silver iodide – ammonia (1/1) 12 AgH3IP 342860 Silver iodide – phosphine (1/1) 13 AlBr3 387274 Aluminum(III) bromide 14 AlCl3 562634 Aluminum(III) chloride 15 AlF3 571004 Aluminum(III) fluoride 16 AlI3 598735 Aluminum(III) iodide 17 Al2Br6 336201 Di-µ-bromotetrabromodialuminum 18 Al2Cl6 229733 Di-µ-chlorotetrachlorodialuminum 19 Al2I6 603842 Di-µ-iodotetraiododialuminum 20 ArH2 170896 Dihydrogen – argon (1/1) 21 AsCl3 242165 Arsenous trichloride 22 AsHO 307008 Oxoarsine 23 AsH2 458081 Arsino 24 AsH2O 214351 Arsenooxy 25 AsH3 246569 Arsine 2,4 26 AsP3 349429 1,2,3-Triphospha-4-arsatricyclo[1.1.0.0 ]butane 27 As2B10H10 345338 1,2-closo-Diarsadodecaborane(10) 28 AuClH2 405051 Chloro(dihydrogen-H,H)gold 29 AuH2IS 500773 Gold(I) iodide – hydrogen sulfide (1/1) 30 BFH 214523 Fluoroborane(2) 31 BFH2O 948395 Fluorohydroxyborane 32 BF2 313328 Difluoroborane(2) 33 BF2HO 139475 Difluorohydroxyborane 34 BH2 138061 Borane(2) 35 BH3O2 496859 Boronic acid © Springer Nature Switzerland AG 2019 903 N.
    [Show full text]