Synthesis, Characterization and Biological Activities of N-(4-(3,4-Dichlorophenoxy)-phenyl)-4-alkoxybenzamide Derivatives

An alkoxy benzamide derivatives are have been synthesized in four steps. Alkylation, halo phenol coupling, nitro group reduction and acid amine coupling gave in decent yield. Likewise, these targets were synthesized by coupling of 4-(3,4-dichlorophenoxy) aniline with N-(4-(3,4-dichlorophenoxy)phenyl)- 4-alkoxybenzamide by using (1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexa fluorophosphate, hexa fluorophosphate azabenzotriazole tetramethyl uronium) (HATU), N,N-diisopropylethylamine (DIPEA) in dimethylformamide (DMF) at 0 ºC to room temperature. Reduction of nitro group in the presence of 10% Pd/C, H2 (g) in MeOH at room temperature. Obtained in decent to excellent yield. Anti-tuberculosis activity of all synthesized derivatives (7a-l) was complete against the H37RV strain as per reported broth dilution method mentioned in experimental section. Bio-assay results showing that derivatives 7c, 7e and 7i exhibited exceptional activity against the H37RV strain with MIC value 62.5 μg/mL. Furthermore, other derivatives were showed poor potency against same strain when compared with standard drugs isoniazid and rifampicin.