1-Styryl-1,3-diketones in the synthesis of spiro[oxindole-3,2'-pyrrolidines] with notable anticancer activity.

A regio- and stereoselective method for the synthesis of spiro[indolin-3,2'-pyrrolidine]-2-ones based on the [3 + 2] cycloaddition of azomethine ylides, generated in situ from isatins and proteinogenic α-amino acids, and (E)-5-arylpent-4-ene-1,3-diones under reflux in methanol within 12 h in 28-91% yields has been developed. A number of representative examples of spiro[indolin-3,2'-pyrrolidine]-2-ones have been studied for cytotoxic activity against HeLa cervical cancer cell line and human dermal fibroblasts (HDF) by the MTT assay. Every investigated compound has shown cytotoxic activity against HeLa cells (IC50 0.24-38.43 μM), while some of them have also shown low cytotoxicity against HDF cells (IC50 100.08-7821.27 μM). A preliminary structure-activity relationship (SAR) correlations have been made.