Synthesis, antitubercular, antimicrobial activities and molecular docking study of quinoline bearing dihydropyrimidines.

In order to develop the antimicrobial and antitubercular agents, we have derived quinoline bearing dihydropyrimidine analogues 5a-o and structures of these compounds were determined by spectroscopic techniques. Further, we have calculated the molecular properties prediction and drug-likeness by Molinspiration property calculation toolkit and MolSoft software, respectively. The most active compound against Mycobacterium tuberculosis (5m, MIC = 0.20 µg/mL) also possessed a maximum drug-likeness model score (0.42). Compounds 5m, 5g and 5k were possessed promising antibacterial activity against tested bacterial species. Compound 5k was the only compound to have eye-catcher antifungal activity. Furthermore, the MTT cytotoxicity results on HeLa cells suggested lower cytotoxicity of biologically active compounds. Supramolecular interactions of the synthesized compounds has been assessed my means of molecular docking studies. Although all the synthesized compounds are showing preferably good interactions with their respective proteins, their binding free energies values suggest that these molecules are preferred for antitubercular activity rather than antimicrobial activity.

Synthesis and antibacterial and cytotoxic activities of new N-3 substituted thiazolidine-2,4-dione derivatives bearing the pyrazole moiety.

Two new series of N-3 substituted thiazolidine-2,4-dione derivatives bearing the pyrazole moiety (5a-j and 7a-j) were synthesized and assessed in vitro for their efficacy as antibacterial agents against gram-positive and gram-negative bacterial strains. Among the tested compounds, 7b, 7c, 7i, and 7j were found to be active against gram-positive bacteria (Staphylococcus aureus and Streptococcus pyogenes) with minimum inhibitory concentration (MIC) values in the range of 6.25-25 µg/mL, and some compounds were also tested against methicillin-resistant S. aureus (MRSA). Compounds 7c and 7j inhibited the growth of MRSA at MIC values of 6.25 and 12.5 µg/mL, respectively. The influence of the lipophilicity (C log P) on the biological profile (MIC) of the prepared products was also discussed. From the standpoint of structure-activity relationship studies, it was observed that the lipophilic profiles of the compounds were crucial for their antibacterial activities. Further, the results of the MTT cytotoxicity studies on a human cervical cancer cell line (HeLa) and a mouse embryonic fibroblast cell line (NIH 3T3) suggested that compounds 7b, 7c, 7i, and 7j were endowed with low levels of cytotoxicity.