Synthesis of 2,5-disubstituted-1,3,4-thiadiazole derivatives from (2S)-3-(benzyloxy)-2-[(tert-butoxycarbonyl) amino] propanoic acid and evaluation of anti-microbial activity

The new compoundsAP-1toAP-10were synthesized from starting material (2S)-3-(benzyloxy)-2-[(tert-butoxycarbonyl) amino]propanoic acid (1). The intermediate 2,5-disubstituted-1,3,4-thiadiazole amine (5) was prepared by coupling of (2S)-3-(Benzyloxy)-2-[(tert-butoxycarbonyl) amino]propanoic acid (1) with pyridine-2-carboxylic acid hydrazide (2) in the presence of carbonyldiimidazole (CDI) followed by 1,3,4-thiadiazole ring formation via diacylhydrazines derivative (3) and deprotection with shorter reaction time and excellent yield. The structures of new compounds were confirmed by spectral analysis. The series of new synthesized compoundsAP-1toAP-10were evaluated for their anti-microbial activitiesin vitroand compoundsAP-1,AP-3,AP-4, andAP-10showed strong activities against all tested microorganisms.