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.