Enantioselective synthesis of chiral 3-alkyl-3-nitro-4-chromanonesviachiral thiourea-catalysed intramolecular Michael-type cyclization

Herein we report an enantioselective method for the rapid construction of chiral 3-nitro-4-chromanonesviaa chiral thiourea-catalyzed intramolecular Michael-type cyclization reaction. With this method, a series of 3,3-disubstituted-3-nitro-4-chromanones bearing contiguous C2/C3 stereocenters were obtained with high diastereoselectivities and good to excellent enantioselectivities.In vitrobiological evaluations indicated that the chiral amide derivative of the product showed more potent antitumor activities than both the racemic and the corresponding enantiomers, showcasing the high influence of enantioselective methodology development toward medicinal studies.