In-vitro antimicrobial screening and molecular docking studies of synthesized 2-chloro-N-(4-phenylthiazol-2-yl)acetamide derivatives

Abstract

Introduction: Glucosamine-6-phosphate (GlcN6P) synthase biosynthetic pathway has been identified as potential targets for the development of new antimicrobial agents. Aim: A series of 2-chloro-N-(42-phenylthiazol-25-yl)acetamide derivatives (3a-r) was synthesized and evaluated their antimicrobial activity. Materials and Methods: The 2-chloro-N-(Para substituted phenylthiazol-25-yl) acetamide (2a-c) were synthesized by stirring intermediates (1a-c) with 2-chloroacetylchloride in dichloromethane in the presence of K2CO3. The intermediate (2a-c) were further reacted with different secondary amine such as pyrrolidine, N-methyl piperazine, N-ethyl piperazine, thiomorpholine, morpholine, piperidine etc in ethanol in presence of TEA Triethylamine (TEA) to get desired compounds (3a-r). Compounds were characterized by a spectroscopic technique such as Fourier transform infraredFTIR, 1 H-NMR, 13 C-NMR, and mass spectrometry. The synthesized thiazole derivatives (3a-r) were screened for anti-bacterial and anti-fungal activity against Escherichia coli, Staphylococcus aureus NCTC 6571, Pseudomonas aeruginosa NCTC 10662, CandidaC. albicans (MTCC-183), AspergillusA. niger (MTCC 281) NCTC 10418 and AspergillusA. flavus (MTCC 277). Result and Conclusion: The results of anti-bacterial screening revealed that among all the screened compounds, eight compounds viz. 3b, 3c, 3d, 3e, 3i, 3j, 3k, and 3p showed moderate to good anti-bacterial and antifungal activity having minimum inhibitory concentration (MIC) between 6.25- and 25 µg/ml. While compound 3d showed the most promising antibacterial activity against E. coli and S. aureus, while the compound 3j showed promising antifungal activity with MIC value 6.25 µg/ml against C. albicans, A. niger and A. flavus. In addition, all these eight potential molecules were also examined for possible binding on enzyme GlcN6Pglucosamine-6-phosphate synthase by molecular docking studies on (PDB ID 1JXA).