Synthesis of Related Compounds of Thiosemicarbazide. VIII. : 5-Mercapto-and 5-Amino-s-triazolo [3, 4-b] [1, 3, 4] thiadiazoles.

Abstract

In order to obtain compounds with hypoglycemic activity, 5-mercapto- (II) and 5-amino-s-triazolo [3, 4-b] [1, 3, 4]-thiadiazoles (VIII) were synthesized by the application of carbon disulfide and cyanogen bromide to 2-hydrazino-1, 3, 4-thiadiazoles (I : R=CH₃, C₂H₅, iso-C₃H₇, C₆H₅). By the application of methyl iodide and cyanogen bromide to the 5-mercapto compounds, in the presence of alkali, 5-methylmercapto compound (III : R'=CH₃) and 5-thiocyano compound (III : R'=CN) were prepared. Oxidative chlorination of the 5-mercapto compound using chlorine gave 5-chlorosulfonyl compound which was aminated to 5-sulfamoyl compound (V). Screening of 5-sulfamoyl (V), 5-mercapto (II), and 5-thiocyano-2-isopropyl-s-triazolo [3, 4-b] [1, 3, 4]-thiadiazole (III'R=iso-C₃H₇ was carried out using alloxan-diabetes mice and 5-sulfamoyl and 5-mercapto compounds were found to have stronger activity than BZ-55 used as control.