Synthesis and Antibacterial Activity of 8-Substituted Phenyl-1-pyridin-3-yl-5H-bis[1, 2, 4]triazolo[3, 4-b； 4＇, 3＇-d][1, 3, 4] thiadiazines

To find new structural leading compounds for the research of the multidrug resistant of antibacterial agents, five novel 8-substituted phenyl-l-pyridin-3-yl-5H-bis1, 2, 4] triazolo3, 4-b;4‘,3‘-d] thiadiazines were prepared from the corresponding intermediates of 3-(5-substituted phenyl1,3,4]oxadiazol-2-ylmethylsulfanyl)-5-pyridin-3-yl-1,2,4]triazol-4-ylamines via intramolecular cyclization and the antibacterial activity in vitro against Gram-postive (G^ ) and Gramnegatiye (G) bacteria was primarily evaluated.