Antimicrobial Properties of Some New Synthesized Benzothiazole Linked Carboxamide, Acetohydrazide, and Sulfonamide Systems

We report herein the interaction of diethylethoxymethylene malonate ( 1 ) with 2‐cyanomethylbenzothiazole ( 7 ) to give diethyl 2‐(2‐benzothiazole‐2‐(3 H )‐ylidiene)‐2‐(cyano ethyl) malonate ( 8a ) in excellent yield. Ethyl 4‐cyano‐1‐oxo‐1 H ‐benzo[4,5]thiazolo[3,2‐ a ]pyridine‐2‐carboxylate (9) was synthesized from 8a and subjected to react with hydrazine hydrate to give its corresponding acid hydrazide 10 . Condensation of 10 with different acid anhydrides afforded the corresponding benzothiazolo pyridine carboxamide derivatives 11 – 15 . In addition, we report a simple synthesis of N ′‐(benzo[ d ]thiazol‐2‐yl)‐2‐((4‐ayl)amino)acetohydrazide derivative ( 17 ), which then reacted with different amines to give the corresponding acetohydrazide derivatives 19a – c . Moreover, compound 17 reacted with some sulfonamide derivatives to give the corresponding sulfonamide derivatives 20 and 22a , b .The newly synthesized compounds were established their structures on the bases of their correct analytical and spectral data and evaluated their antimicrobial activity. It was found that compounds 22a , b displayed the highest antimicrobial activity against the tested organisms.