HETEROCYCLIC-SYSTEMS CONTAINING BRIDGEHEAD NITROGEN ATOM - SYNTHESIS AND BIOACTIVITY OF S-TRIAZOLO [3,4-B] [1,3,4] THIADIAZOLE, S-TRIAZOLO [3',4'-B] [1,3,4] THIADIAZINE AND S-THIAZOLO [3',4' 2,3] [1,3,4]THIADIAZINO [5,6-B] QUINOXALINE/

Condensation of 3-m-methoxyphenyl-5-mercapto-s-triazole (2) with chlor oacetic acid, alpha-haloketone, benzoin and 2,3-dichloroquinoxaline fu rnished 3-m-methoxyphenyl-5H-s-triazolo [3,4-b] [1,3,4] thiadiazin-6-( 7H)-one (3), 3,6-disubstituted-7H-s-triazolo [3,4-b] [1,3,4] thiadiazi nes (4), 3-m-methoxyphenyl-6,7-diphenyl-5H-s-triazolo [3,4-b] [1,3,4] thiadiazine (5) and 3-m-methoxyphenyl-5H-s-triazolo [3',4':2,3] [1,3,4 ] thiadiazino [5,6-b] quinoxaline (6). The reaction of 2 with isonicot inic acid and carbon disulphide furnished 3-m-methoxyphenyl-6-(4-pyrid yl)-s-triazo [3,4-b] [1,3,4] triazole (7) and 3-m-methoxyphenyl-s-tria zolo [3,4-b] [1,3,4] thiadiazol-6(5H)-thione (8) respectively. The ant ibacterial and antifungal activity of some of the compounds have also been evaluated.