Dihydropyrimidinones: efficient one-pot green synthesis using Montmorillonite-KSF and evaluation of their cytotoxic activity.

A simple, efficient, cost-effective, recyclable and green approach has been developed for the synthesis of new dihydropyrimidinone analogs the Biginelli reaction. The methodology involves a multicomponent reaction catalyzed by "HPA-Montmorillonite-KSF" as a reusable and heterogeneous catalyst. This method gives an efficient and much improved modification of the original Biginelli reaction, in terms of yield and short reaction times under solvent free conditions. All the derivatives were subjected to cytotoxicity screening against a panel of four different human cancer cell lines . colon (Colo-205), prostate (PC-3), leukemia (THP-1) and lung (A549) to check their effect on percentage growth. MTT [3-(4,5-dimethylthiazol-yl)-diphenyl tetrazoliumbromide] cytotoxicity assay was employed to check IC values. Of the synthesized analogs, 16a showed the best activity with IC of 7.1 ± 0.8, 13.1 ± 1.4, 13.8 ± 0.9 and 14.7 ± 1.1 μM against lung (A549), leukemia (THP-1), prostate (PC-3) and colon (Colo-205) cancer lines, respectively. The 16a analog was further checked for its effect on cancer cell properties through clonogenic (colony formation) and scratch motility (wound healing) assays and thereby was found that it reduced both the colony formation and migratory properties of the lung cancer cell line (A549). Further, molecular docking studies were performed with 16a to show its binding mode.