- Synthesis and anti-microbial activity of isothiosemicarbazones and cyclic analogues.
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It is known that some derivatives of both thiourea and thiosemicarbazide exhibit potent anti-microbial activity. In order to investigate the effects on the biological properties of structural modifications of such structures, we have synthesised and studi
- Maccioni,Cardia,Bonsignore,Plumitallo,Pellerano,De Logu
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- 4-Aralkyl-5-substituted-1,2,4-triazole-5-thiols
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Compounds of formula (I) and pharmaceutically acceptable salts thereof are described in which, n is 0 to 5; X1 to X5 are any accessible combination of hydrogen, halogen, C1 6alkyl, C1 6alkoxy, cyano, nitro, SONH2, SO2NH2, SO2CH3, SO2CH2F, SO2CHF2, SO2CF3, CF3, CHO, OH, CH2OH, CO2H, or CO2CpH2p+1wherein p is 1 to 4; R1 is phenyl substituted by X1 to X5, C1 4alkyl, C3 6cycloalkyl, or an arylC1 4alkyl group substituted by X1 to X5; R2 is hydrogen, C1 4alkyl or (CH2)m-CO2R3; m is 0 to 5; and R3 is H or C1 4alkyl. These compounds are dopamine-β-hydroxylase inhibitors. Pharmaceutical compositions are described as are methods of use. Processes for the preparation of these compounds are described.
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- Oxidation and Eliminative Cyclisation of S-Alkylisodithiobiureas
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Isothiocyanates condense with S-alkylisothiosemicarbazides to yield S-alkylisodithiobiureas.These undergo cyclisation to give 3-amino-5-mercapto-4-substituted-1,2,4-triazoles with the elimination of alkyl mercaptan on heating under neutral conditions, whereas under acidic conditions, by elimination of ammonia 5-alkylmercapto-2-substituted amino-1,3,4-thiadiazoles are formed.Condensation of isothiocyanates with thiosemicarbazides in the presence of alkali affords 1-substituted dithiobiureas.Alkylation of these dithiobiureas with alkyl halides results in the formation of 5-alkylmercapto-2-substituted-amino-1,3,4-thiadiazoles, any intermediateproduct not being isolable.On the other hand, oxidation of 1-substituted dithiobiureas with either hydrogen peroxide or iodine furnishes 2-amino-5-substituted-amino-1,3,4-thiadiazoles.
- Indukumari, P. V.,Joshua, C. P.,Rajan, V. P.
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p. 384 - 387
(2007/10/02)
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