Novel 1,4-dihydropyrano[2,3-c]pyrazole derivatives: Synthesis, characterization, biological evaluation and in silico study

Abstract

In the present study, a series of novel and biologically potent 6-amino-1-(2,4-dinitrophenyl)-4-phenyl-1,4-dihydropyrano [2,3-c]pyrazole-5-carbonitrile derivatives (5a-5u) have been synthesized through multicomponent reaction between various substituted aromatic aldehyde derivative (4a-4u), 2, 4-dinitrophenyl hydrazine (1), ethyl acetoacetate (2) and malononitrile (3) in the presence of SnCl2 as a prompt catalyst using both microwave irradiation method as well as conventional method. The structure of synthesized compounds were confirmed by various spectroscopic methods such as 1H NMR, 13C NMR, IR, Mass analysis and elemental analysis. All the synthesized compounds were subjected in vitro antibacterial, anti-tuberculosis screening and cytotoxicity MTT assay. In vitro biological study revealed that the synthesized compound 5a, 7a and 8a are showing good anti-bacterial and anti-tuberculosis activity. The in silico study of ADME pharmacokinetic properties were also predicted for synthesized compounds for checking their bioavailability. Furthermore, molecular docking study of synthesized compounds with enoyl-ACP reductase (oxidoreductase) was carry out to find out the binding affinity of compounds. Docking study demonstrated that compound 7b and 7a possessed superior binding affinity with target enzyme by strong hydrogen bonding. We have also carried out molecular dynamics simulation to check the stability of docked complex, conformational changes and primary molecular interaction.