Multicomponent assembly of novel antiproliferative steroidal dihydropyridinyl spirooxindoles

Abstract Multicomponent assembly of steroidal dihydropyridinyl spirooxindoles from pregnenolone, isatins, malononitrile, and ammonium acetate is described, which involves the formation of two C–C bonds, two C–N bonds, and an all-carbon quaternary stereogenic center in a single operation. MTT assays showed that some of these compounds had moderate to excellent cytotoxicity against the tested cancer cell lines and were more potent than 5-FU. Particularly, compound 5o represented excellent inhibitory effect toward EC-109 (IC 50  = 0.3 μM), being about 33-fold more potent than 5-FU.