Synthesis, characterization, mechanistic study, in-vitro and in-silico evaluation of antibacterial and antioxidant activities of novel pyrazole-pyrazoline hybrid systems

This study describes the synthesis, characterization, and in vitro as well as in silico assessment of the biological activity of a new series of hybrid molecules. These target compounds were synthesized via a highly regioselective 1,3-dipolar cycloaddition (1,3-DC) reaction. The structures of the resulting hybrids were elucidated through conventional spectroscopic techniques and the x-ray crystal structure of one member. The mechanism of the 1,3DC reaction and its regioselectivity were explained using theoretical studies. The pyrazole-pyrazoline conjugates underwent testing for antibacterial efficacy against three pathogenic bacterial strains and demonstrated an effective action against them. The conjugates were assessed for their antiradical potential and the findings suggest that these conjugates exhibit a significant capacity for scavenging free radicals. Moreover, molecular docking investigations were carried out to support the experimental findings and identify likely interactions involving pyrazole-pyrazoline hybrids and target proteins. Subsequently, 100 ns molecular dynamics (MD) simulations were undertaken to examine the stability of the resulting protein-ligand complexes.