Synthesis of Medicinally Important N-Trimethylene Dipiperidine Sulfonamides and Carboxamides Containing a Substituted Benzophenone Moiety - An Antibacterial Agents

A series of novel substituted 2-[4-(2,4-dimethoxy-benzoyl)-phenoxy]-1-[4-(3-piperidin-4-yl-propyl)-piperidin- 1-yl]-ethanone sulfonamide (9a-h) benzamides (10a-h) were synthesized in order to determine their antibacterial activities and possible structure- activity relationships to improve therapeutic efficacy. The synthesized compounds were characterized by 1H-NMR, FTIR and elemental analysis. All the synthesized compounds were evaluated in vitro for their efficacy as antibacterial agents by agar well diffusion and micro dilution method against standard strains of Gram-positive (staphylococcus aureus ATCC 29737, Bacillus substilis NCIM 2010, Streptococcus pyognes NCIM 2608) and Gram-negative (Pseudomonas aeruginosa ATCC 20852, Klebsiella pneumoniae MTCC 618, Escherichia coli ATCC 25922) bacteria. Among the synthesized new compounds (9c), (9d), (9e), (9f), (10a), (10c), (10d), (10e) and (10g) showed potent antibacterial activities compared to the standard drug. In particular, all the tested compounds had potent inhibitory activity against B. subtilis and E. coli.