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Tomas Torroba - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of [1,3]Dithiole and Spiro[1,3]dithiole Thiopyran Derivatives of the [1,2]Dithiolo[1,4]thiazine Ring System
Journal of Organic Chemistry, 2002Co-Authors: Susana Barriga, Pedro Fuertes, Carlos F. Marcos, Oleg A. Rakitin, Tomas TorrobaAbstract:We report the synthesis of some new polysulfur−nitrogen heterocycles by cycloaddition reactions to readily available tricyclic condensed 1,2-dithiole-3-thiones. Thus, treatment of bis[1,2]dithiolopyrrole ketothione 1 with diacyl acetylenes gave the bis-aducts 2a−d. On the other hand, cycloaddition of bis[1,2]dithiolo[1,4]thiazine ketothione 3 with 1 equiv of acyl or diacyl acetylenes gave [1,3]dithiolylidenyl[1,2]dithiolo[1,4]Thiazines 4a−f in fair to high yields. Catalysis by scandium triflate was used in the reactions that implied the less reactive dipolarophiles. Treatment of 3 with 2 equiv of DBA gave the bis-aduct 5a, and reaction of 4c with DMAD gave the mixed bis-adduct 5b. Cyclic voltammetry of selected examples showed irreversible processes that were influenced by the electrochemical activity of peripheral groups bonded to the heterocyclic system.
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Synthesis of Thiadiazole, Dithietane, and Imine Derivatives of the [1,2]Dithiolo[1,4]thiazine Ring System
Journal of Organic Chemistry, 2001Co-Authors: Susana Barriga, Pedro Fuertes, Carlos F. Marcos, Daniel Miguel, Charles W. Rees, Oleg A. Rakitin, Tomas TorrobaAbstract:We report the synthesis of some new polysulfur−nitrogen heterocyclics by cycloaddition reactions to the thioketo group of readily available tricyclic 1,2-dithiole-3-thiones. Thus treatment of bis[1,2]dithiolo[1,4]thiazine ketothione 1 with diaryl nitrile imines generated from hydrazonoyl chlorides 2a−g gave [1,3,4]thiadiazolylidenyl[1,2]dithiolo[1,4]Thiazines 4a−g in high yield. Compounds 4a−f, bearing the same substituents in both aryl groups, were stable but the analogous 4g,h with a p-nitrophenyl group on carbon gave the bis[1,2]dithiolo[1,4]thiazine dione 9, probably by cycloreversion and hydrolysis during chromatography. Treatment of 1, the bis[1,2]dithiolopyrrole ketothione 13, and dithione 12 with ethoxycarbonyl azide 11 gave imines 12 and 15 and bisimine 16, respectively, by an alternative fragmentation of the initial cycloadduct in which the 1,2-dithiole ring is retained. Reaction of 1 with TosMIC gave the imino-1,3-dithietane 17.
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synthesis of n unsubstituted bis 1 2 dithiolo 1 4 Thiazines and bis 1 2 dithiolopyrroles
ChemInform, 2001Co-Authors: Lidia S Konstantinova, Charles W. Rees, Oleg A. Rakitin, Natalia V Obruchnikova, Tomas TorrobaAbstract:The parent bis[1,2]dithiolo[1,4]thiazine-3,5-dione 8, -3,5-dithione 11, the unsymmetrical 3-oxo-5-thione 10 and the bis[1,2]dithiolopyrrole-3,5-dione 9 are synthesised by acid catalysed cleavage of their various N-benzyl, ethyl, ethoxycarbonylethyl and propanoic acid derivatives. These N-alkyl compounds are prepared in the usual way from the appropriate N-alkyldiisopropylamine and S2Cl2. N-Benzyl derivatives 2 and 5 of the thiazine and pyrrole diones give 8 (100%) and 9 (58%) respectively with conc. H2SO4 in dilute DCM solution, and the N-ethyl thiazine derivatives of the dione 12 and the keto-thione 13 give 8 (89%) and 10 (75%) respectively in conc. H2SO4 at 120 °C. Ethyl 3-(diisopropylamino)propanoate 16 with S2Cl2 gives the three Thiazines 17 (30%), 18 (15%) and 19 (13%), and 17 and 19 are converted into the pyrroles 20 (95%) and 21 (90%) respectively by thermal extrusion of sulfur in refluxing xylene. All five ethyl esters, 17–21, are hydrolysed with aqueous acid to 22–26 respectively in 92–100% yield, and the N-propanoic acids 22–25 with hot conc. hydrochloric or hot 80–90% sulfuric acid are dealkylated to the corresponding parent products 8–11. It is also shown that the hydrolysis and dealkylation steps 17→22→8 can be combined in one operation (75%).
Martin Schlitzer - One of the best experts on this subject based on the ideXlab platform.
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iminium carbonic acid derivative salts ix synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium salts part 1 preparation of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazoliu
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-Thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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iminium carbonic acid derivative salts xi synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazouum salts part 3 reaction of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium sa
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]Thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium carbonic acid derivative salts. IX. Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazolium salts part 1. Preparation of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazo
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-Thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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Iminium carbonic acid derivative salts. XI . Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoüum salts. Part 3. Reaction of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoli
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]Thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
Jean-claude Meslin - One of the best experts on this subject based on the ideXlab platform.
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FORMATION DE 2H-1,4-Thiazines, 2-BENZYLTHIAZOLES ET 2-BENZOYLTHIAZOLES PAR ACTION DE LA SILICE SUR LES 4-AMINO-3,4-DIHYDRO-2H-1,4-Thiazines
Phosphorus Sulfur and Silicon and the Related Elements, 1993Co-Authors: R. Besbes, A. Reliquet, F. Reliquet Et, Jean-claude MeslinAbstract:Abstract In the presence of silica, 4-dimethylamino-3,4-dihydro-2H-1,4-Thiazines 1 afford 2H-1,4-Thiazines 2 with good yields, 2-benzyl-4-methoxycarbonylthiazoles 3 or 2-aroyl-4-methoxycarbonylthiazoles 4 depending on substituents bound to the thiazinic cycle and experimental conditions. As for 2H-1,4-Thiazines 2, they give rise to bisThiazines by a duplication reaction. Les 4-dimethylamino-3,4-dihydro-2H-1,4-Thiazines 1, traitees par la silice, permettent d'obtenir, en fonction des substituants presents sur le cycle thiazinique et des conditions experimentales choisies, soit les 2H-1,4-Thiazines 2 avec d'excellents rendements, soit les 2-benzyl-4-methoxycarbonylthiazoles 3, soit les 2-aroyl-4-methoxycarbonylthiazoles 4. Les 2H-1,4-Thiazines 2, quant-a elles, fournissent par une reaction de duplication les bisThiazines 5.
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4H-1,4-Thiazines ET 2H-1,4-Thiazines A PARTIR DE 2-(DIALKYLHYDRAZONO)-THIOACETOPHENONES
Phosphorus Sulfur and Silicon and the Related Elements, 1992Co-Authors: A. Reliquet, R. Besbes, Francoise Reliquet, Jean-claude MeslinAbstract:Abstract 2-(Dialkylhydrazono)thioacetophenones 1 react with N-phenylmaleimide and lead via [4 + 2] cycloaddition to 4-amino-3,4-dihydro-2H-1,4-Thiazines 2 which are easily converted into 4H-1,4-Thiazines 3. Reaction with 1,4-naphthoquinone leads directly to 4H-1,4-Thiazines 4. Acetylenic dienophiles as methyl propiolate or dimethyl acetylenedicarboxylate authorize synthesis of 2-amino-2H-1,4-Thiazines 5 after amino group transposition. Reaction with diethyl azodicarboxylate gives rise to new hydrazonothioacetophenones 6, rather unstable, which can undergo [4 + 2] cycloaddition with methyl acrylate leading to 3,4-dihydro-2H-1,4-Thiazines 7. Les 2-(dialkylhydrazono)thioacetophenones 1 reagissent avec le N-phenylmaleimide pour donner, par cycloaddition [4 + 2], les 4-amino-3,4-dihydro-2H-1,4-Thiazines 2 qui sont aisement converties en 4H-1,4-Thiazines 3. La reaction avec la 1,4-naphtoquinone conduit directement aux 4H-1,4-Thiazines 4. Les dienophiles acetyleniques comme le propiolate de methyle ou l′acetylen...
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The Heteroatomic Chains and Their Derived Cyclic Products XI.1 A Synthesis of 2-(Dialkylhydrazono)thioacetophenones as Agents in the Preparation of 3,4-Dihydro-2H-1,4-Thiazines and 2H-1,4-Thiazines
Synthesis, 1991Co-Authors: Alain Reliquet, Francoise Reliquet, Rafaa Besbes, Jean-claude MeslinAbstract:We describe the preparation of 2-(dialkylhydrazono)-thioacetophenones starting from their oxygenated analogs. These compounds are used as building blocks in heterocyclic chemistry and lead to 3,4-dihydro-2H-1,4-Thiazines or 2H-1,4-Thiazines
Wolfgang Hanefeld - One of the best experts on this subject based on the ideXlab platform.
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iminium carbonic acid derivative salts ix synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium salts part 1 preparation of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazoliu
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-Thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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iminium carbonic acid derivative salts xi synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazouum salts part 3 reaction of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium sa
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]Thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium carbonic acid derivative salts. IX. Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazolium salts part 1. Preparation of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazo
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-Thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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Iminium carbonic acid derivative salts. XI . Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoüum salts. Part 3. Reaction of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoli
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]Thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Untersuchungen an 1,3‐Thiazinen, 44. Neuartige Umlagerungsreaktion von 3,3′‐Carbonylbis(tetrahydro‐2H‐1,3‐thiazin‐2‐thion) und 3,3′‐Carbonylbis(2‐thiazolidinthion)2)
Liebigs Annalen der Chemie, 1991Co-Authors: Wolfgang Hanefeld, Hans Joachim Von GösselnAbstract:Investigations of 1,3-Thiazines, 44. – Novel Rearrangement of 3,3′-Carbonylbis(tetrahydro-2H-1,3-thiazine-2-thiozine) and 3,3′-Carbonylbis(2-thiazolidinethione)2) 2-Thioxo-1,3-thiazine and -thiazolidine derivatives react with phosgen yielding N,N′-carbonylbis(heterocycles) 3, 9, 11, 12. With excess of phosgen 3 and 9 gave a novel rearrangement to the 3,5-bis(ω-chloroalkyl)-2,6-dithioxo-perhydro-1,3,5-thiadiazin-4-ones 8 and 10.
Susana Barriga - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of [1,3]Dithiole and Spiro[1,3]dithiole Thiopyran Derivatives of the [1,2]Dithiolo[1,4]thiazine Ring System
Journal of Organic Chemistry, 2002Co-Authors: Susana Barriga, Pedro Fuertes, Carlos F. Marcos, Oleg A. Rakitin, Tomas TorrobaAbstract:We report the synthesis of some new polysulfur−nitrogen heterocycles by cycloaddition reactions to readily available tricyclic condensed 1,2-dithiole-3-thiones. Thus, treatment of bis[1,2]dithiolopyrrole ketothione 1 with diacyl acetylenes gave the bis-aducts 2a−d. On the other hand, cycloaddition of bis[1,2]dithiolo[1,4]thiazine ketothione 3 with 1 equiv of acyl or diacyl acetylenes gave [1,3]dithiolylidenyl[1,2]dithiolo[1,4]Thiazines 4a−f in fair to high yields. Catalysis by scandium triflate was used in the reactions that implied the less reactive dipolarophiles. Treatment of 3 with 2 equiv of DBA gave the bis-aduct 5a, and reaction of 4c with DMAD gave the mixed bis-adduct 5b. Cyclic voltammetry of selected examples showed irreversible processes that were influenced by the electrochemical activity of peripheral groups bonded to the heterocyclic system.
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Synthesis of Thiadiazole, Dithietane, and Imine Derivatives of the [1,2]Dithiolo[1,4]thiazine Ring System
Journal of Organic Chemistry, 2001Co-Authors: Susana Barriga, Pedro Fuertes, Carlos F. Marcos, Daniel Miguel, Charles W. Rees, Oleg A. Rakitin, Tomas TorrobaAbstract:We report the synthesis of some new polysulfur−nitrogen heterocyclics by cycloaddition reactions to the thioketo group of readily available tricyclic 1,2-dithiole-3-thiones. Thus treatment of bis[1,2]dithiolo[1,4]thiazine ketothione 1 with diaryl nitrile imines generated from hydrazonoyl chlorides 2a−g gave [1,3,4]thiadiazolylidenyl[1,2]dithiolo[1,4]Thiazines 4a−g in high yield. Compounds 4a−f, bearing the same substituents in both aryl groups, were stable but the analogous 4g,h with a p-nitrophenyl group on carbon gave the bis[1,2]dithiolo[1,4]thiazine dione 9, probably by cycloreversion and hydrolysis during chromatography. Treatment of 1, the bis[1,2]dithiolopyrrole ketothione 13, and dithione 12 with ethoxycarbonyl azide 11 gave imines 12 and 15 and bisimine 16, respectively, by an alternative fragmentation of the initial cycloadduct in which the 1,2-dithiole ring is retained. Reaction of 1 with TosMIC gave the imino-1,3-dithietane 17.
