3,6-DISUBSTITUTED 1,2,4-TRIAZOLO[3,4-B][1,3,4]THIADIAZOLES - SYNTHESIS AND EVALUATION FOR ANTIMICROBIAL AND ANTIVIRAL ACTIVITY .3.

A series of novel 3,6-disubstituted 1,2,4-triazolo[3,4-b][1,3,4]thiadi azole derivatives was prepared and tested to evaluate their antimycoti c, antibacterial and anti-HIV-1 activities. The reaction of thio-carbo hydrazide with carboxylic acids at the melting temperature allows an i mproved preparation of the 5-substituted 4-amino-3-mercapto-1,2,4-tria zole heterocycles which in turn allows an easier preparation of the 1, 2,4-triazolo[3,4-b] [1,3,4]thiadiazole ring system. All tested compoun ds didn't show any significant activity.