Synthesis and antiproliferative studies of curcumin pyrazole derivatives

A series of curcumin pyrazole derivatives ( 3a–e ) were synthesized. The chemical structures were determined by 1 H and 13 C NMR spectroscopic techniques and their purity was confirmed by LC–MS and melting point determination. The compounds were screened for anticancer effects on different cancer cell lines by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. The analogs demonstrated growth inhibitory effect on MCF-7, HeLa, and K562 cell lines with significant IC 50 values. Compound 3b exhibited a high degree of cytotoxicity against cancer cells and minimum growth inhibitory effects against normal cells HEK293T and hence further, cell cycle analysis and mitochondrial membrane potential studies (JC-1 assay) were conducted by utilizing flow cytometry against K562 cells. This compound effectively arrested cell cycle progression at SubG1 phase and cells exhibited decreased membrane potential in a concentration-dependent manner with fluorescence shifting from red to green. Our findings suggest that compound 3b could be a promising anticancer agent since it effectively inhibited cell proliferation and can be selected for further in vitro and in vivo investigations.