Synthesis and biological evaluation of new benzothiazoles as antimicrobial agents

A new series of hydrazide derivatives were synthesized, characterized, and biologically evaluated. The reaction of 2-chloro benzo[ d ]thiazole 1 , with ethyl 2-(piperazin-1-yl) acetate 2 , led to the formation of ethyl 2-(4-(benzo[ d ]thiazol-2-yl)piperazin-1-yl)acetate 3 . The reaction of compound 3 with excess amount of hydrazine hydrate gave 2-(4-(benzo[ d ]thiazol-2-yl) piperazin-1-yl) acetohydrazide 4 . Hydrazide derivatives 5 ( a – j ) were prepared by the reaction of compound 4 with the appropriate acid chloride. The in vitro antibacterial activity of compounds 3 , 4 , 5a , and 5b were screened against Staphylococcus aureus , Escherichia coli , and Candida albicans bacteria, no activity has been witnessed.