In an effort to discover new candidates with improved antimicrobial activities we report here the synthesis and in vitro biological evaluation of various series of 2-{(3,4,5-trimethoxy phenyl-1,3,4-oxadiazolyl)-5-thio}-4-(morpholino)-6-(phenyl ureido)-striazine (7a-i) and 2-{(3,4,5-trimethoxy phenyl-1,3,4-oxadiazolyl)-5-thio}-4-(morpholino)-6-(phenyl thioureido)-s-triazine (8a-g). Antimicrobial properties of the title compounds were investigated against two Gram ( þ ve) bacteria (S. aureus, B. subtilis), two Gram (2ve) bacteria (P. aeruginosa, E. coli) and yeast-like fungi (C. albicans) using the broth microdilution method.

Some new substituted quinolinyl chalcones were synthesized and evaluated for their in vitro antimicrobial activity against Gram positive and Gram negative strains using a microdilution procedure. Synthesized compounds 10a-g and 13h-q prove to be effective with MIC (mg ml -1 ), among them 10a, 10b, 10c, 13I, 13p showed excellent activity against a panel of microorganisms. The newly synthesized compounds were characterized using IR, 1 H-NMR and elemental analysis.