Synthesis and Microbial Studies of New Pyridine Derivatives‐III

Abstract

Abstract2‐Amino substituted benzothiazole 4a–4l and p‐acetamidobenzenesulfonyl chloride 2 were used to prepare 2‐(p‐aminophenylsulfonamido) substituted benzothiazole 6a–6l using mixture of pyridine and acetic anhydride which formed an electrophilic complex (N‐acetyl pyridinium) to facilitate condensation to give desired product by removal of HCl. 2‐{p‐[(3‐Carboxypyrid‐2‐yl)amino]phenylsulfonamido}benzothiazoles 8a–8l were synthesized from 2‐chloropyridine‐3‐carboxylic acid 7 and 6a–6l in 2‐ethoxy ethanol using Cu‐powder and K2CO3. Acid chlorides 9a–9l were condensed with 2‐hydroxyethyl piperazine 10 and 2,3‐dichloropiperazine 11 for amide derivatives 2‐(p‐((3‐(4‐(2‐hydroxyethyl)piperazin‐1‐ylcarbonyl)pyrid‐2‐yl)amino)phenylsulfonamido)benzothiazoles 12a–12l and 2‐{p‐[3‐(2,3‐dichloropiperazin‐1‐ylcarbonyl)pyrid‐2‐ylamino]phenylsulfonamido}benzothiazoles 13a–13l respectively. The structures of the new compounds have been established on the basis of their chemical analysis and spectral data (IR, 1H NMR and mass). All the compounds have been screened for their antibacterial and antifungal activities.