Synthesis of Novel Thiadiazoles and Triazoles from Salicylaldehyde derivatives and Evaluation of their Antimicrobial Activity

Abstract

Salicylaldehyde and its derivatives were reacted with phenyl hydrazine affording salicylaldehyde phenyl hydrazones (3a-b). The latter were reacted with different reagents including NBS to give hydrazonyl halides (4a-b). Also, treatment of the hydrazones 3a-b with potassium thiocyanate in hot ethanol afforded 1,3,4- thiadiazole imines (5a-b) and their hydrolysis gave (6a-b). The hydrazones 3a-b  were also treated with 4-(6-phenylpyrimidine-2-thione) and triethylamine (TEA) in cold water affording 1,2,4,5 triazoles (7a-b). The physical and spectral data have been explained and biological screening of these derivatives for their antibacterial activity against various microorganism have been measured.

Keywords Salicylaldehyde, Phenyl Hydrazine, Thiadiazoles, Triazoles, Antibacterial activity.