Synthesis, DNA binding and in-vitro cytotoxicity studies on novel bis-pyrazoles

A new series of bis-pyrazoles 6a-t were synthesized from 3,5-dimethyl pyrazole using sequential approach. All these compounds were characterized by IR, ¹H NMR, ¹³C NMR and mass spectral data. The interaction of newly synthesized bis-pyrazoles with DNA was investigated through molecular docking and absorption spectroscopic technique. Among all bis-pyrazoles compounds, the 6h compound showed lower conformational energy through in silico analysis. The interaction of each molecule in this series 6a-t with the various concentrations of DNA was examined through the UV-visible spectroscopic studies. The UV-visible spectroscopy studies on the specific binding of compound 6a, 6b, 6g, 6h, 6d, 6i, 6k, 6n, 6s with DNA have exhibited spectral shifts and the results were discussed. In further the compounds 6a-t were subjected to the in-vitro cytotoxicity studies against human pancreatic adenocarcinoma, human non-small cell lung carcinoma cell lines. Among the screened compounds, N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-1H-pyrazol-1-yl)-1H-pyrazol-5-yl)cyclobutane carboxamide and N-(5'-Isopropoxy-2'-isopropyl-3,5-dimethyl-2'H-[1,4'] bipyrazolyl-3'-yl)-dimethane sulfonamide were found as lead molecules since they have exhibited promising activity against both the cancer cell lines used in this study, whereas the compounds 4-(trifluoromethyl)-N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-2H-pyrrol-2-yl)-1H-pyrazol-5-yl)benzamide and 2,6-difluoro-N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-2H-pyrrol-2-yl)-1H-pyrazol-5-yl) benzamide were found to be active against the pancreatic cell line only. Rest all the other compounds were found to exhibit moderate to good activity towards both the cell lines.