SYNTHESIS AND CHARACTERIZATION OF SOME 2,5-DISUBSTITUTED 1,3,4-THIADIAZOLES - 2-MERCAPTO-DERIVATIVE AND 2-ALKYLMERCAPTODERIVATIVE

The new rcapto-5-p(arylsulphonyl)phenyl-1,3,4-thiadiazoles I-e existin g mainly in their thionic tautomeric form 1B - were synthesized by aci d catalyzed cyclization of corresponding potassium acyldithiocarbazina tes 4. Various S-alkylmercapto-1,3,4-thiadiazoles 1d-h, derived from 1 a-c were obtained by two methods. The -5-p(bromophenylsulphonyl)phenyl -1,3,4-thiadiazole (1c) showed a dichotomous behaviour in alkylation, affording S-alkyl (li-k) and N-alkyl (8a-c) derivatives. The new compo unds were characterized by their IR-, UV- and H-1-NMR spectra.