Synthesis, spectral characterization of pyrazole derived Schiff base analogs: molecular dynamic simulation, antibacterial and DNA binding studies.

We have synthesized the pyrazole-bearing Schiff base derivatives ( 5a-5e ) and ( 6a-6h ) then the structural confirmation was supported by various spectral analyses. The antibacterial activity of all analogs was screened against bacterial strains Staphylococcus aureus , Bacillus subtilis , Enterococcus faecalis , Escherichia coli , Klebsiella pneumonieae and Pseudomonas aeruginosa . In comparison to the reference drug ciprofloxacin, the lead analogs 5c and 6c showed potent activity, with MIC values of 64 µg/mL against E. coli and B. subtilis . Compound 5c showed a moderate effect with a MIC value of 128 µg/mL against B. subtilis , P. aeruginosa and K. pneumonieae , while compound 6c was against E. coli and P. aeruginosa. Furthermore, the compounds 5c and 6c displayed groove binding mode towards CT-DNA by absorption, emission, competitive fluorescence studies using EtBr, CD and time-resolved fluorescence studies. Thermodynamic parameters of analogs 5c and 6c with CT-DNA were also calculated at 298, 303 and 308K temperatures by UV-visible spectroscopy. The molecular docking studies give the docking score for all compounds with PDB codes: 1BNA and 2XCT. The MD simulation study of analogs 5c and 6c was also carried out. The pharmacokinetic and ADME properties were calculated for all of the synthesized analogs ( 5a-5e ) and ( 6a-6h ).Communicated by Ramaswamy H. Sarma.