Synthesis, structural and pharmacological exploration of 2-(3, 5-dimethyl-1H-pyrazol-1-yl)-acetophenone oximes and their silver complexes

Abstract Some new compounds, 2-(3,5-dimethyl-1H-pyrazol-1-yl)-4-substituted acetophenone oximes [4a-4f; here, 4-substituent = H (a), Br (b), Me (c), Cl(d), NO2 (e), F (f)] were synthesized by the reaction of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-1-arylethanones with hydroxylamine hydrochloride. These compounds were characterized by analyzing their IR, 1H, 13C NMR and mass spectral data. Compounds 4a-4f were further converted into their silver complexes (4g-4l) and chemical structures of which were established on the basis of their X-ray crystallographic data. The antibacterial and DNA photocleavage activity studies were carried out for all the synthesized compounds 4a-4l, and it has been found that compound 4l displayed an excellent level of antibacterial and DNA photocleavage activity. Among the series, Ag-complexes (4g-4l) displayed excellent antibacterial activity against four bacterial strains using Ciprofloxacin as a standard drug. In DNA photocleavage study, it has been observed that compounds 4a, 4e, 4f degraded both forms of DNA, whereas their Ag-complexes degraded DNA completely even at a very low concentration. The intermolecular interactions present in 4g and 4h were described by decomposing Hirshfeld surfaces into 2D fingerprint plots. It was observed that non-polar interactions contribute dominantly in overall intermolecular interactions exit in crystals of both the compounds.