SYNTHESIS OF SOME BENZOFURAN DERIVATIVES OF SYM-TRIAZOLO[4,3-B]-1,2,4-TRIAZOLE, SYM-TRIAZOLO[3,4-B]-1,3,4-THIADIAZOLE AND SYM-TRIAZOLO[3,4-B]-1,3,4-THIADIAZINE SYSTEMS

4-Amino-3(2-benzofuranyl)-5-mercapto-1,2,4-triazole (I) undergoes ring closure with carbon disulphide, acid chlorides, aldehydes, isocyanates, and chloroacetic acid to give the corresponding s-triazole-fused heterocycles. Various nucleophilic displacement reactions of these compounds obtained have been investigated.