Synthesis and Biological Evaluation of Some [1,2,4]Triazolo[3,4-b][1,3,4]Thiadiazoles and [1,2,4]Triazolo[3,4-b][1,3,4]Thiadiazines

The reaction of 2-(aryloxymethyl)benzoic acid hydrazide with carbon disulfide in the presence of potassium hydroxide followed by hydrazine hydrate afforded 4-amino-3{2-(aryloxymethyl)pheny}[1,2,4]triazole-5-thiol (5a-d). The cyclo-condensation of 5a-d with various aromatic carboxylic acids in the presence of phosphorous oxychloride and with phenacyl bromides afforded two series of fused heterocycles namely; 6-substituted-3-{2-(aryloxymethyl)phenyl}-1,2,4- triazolo[3,4-b][1,3,4]thiadizoles (6a-t) and 6-substituted-3-{2-(aryloxymethyl)phenyl)}[1,2,4]triazolo[3,4-b][1,3,4] thiadiazines (7a-p) respectively. The structures of these newly synthesized compounds were established on the basis of their IR, 1H-NMR 13C-NMR and Mass spectral data. All the title compounds were screened for their antimicrobial and antiinflammatory activities. Preliminary results indicated that some of them exhibit promising activities and they deserve more consideration as potential antimicrobial and anti-inflammatory agents.