Asymmetric Synthesis of Multicyclic Spirooxindole Derivatives Bearing Stereogenic Quaternary Carbon Atoms

An organocatalyzed stereoselective domino reaction as a facile approach to multicyclic spirooxindole derivatives bearing two stereogenic quaternary carbon atoms is reported. The alkyl substituted chiral thiourea catalyst was efficient for the reaction to tolerate a wide range of substrates, furnishing a new class of spirooxindole derivatives bearing an O,O-acetal-fused tricyclic skeleton or tetrahydroxanthone moiety in moderate to good yields with good to excellent selectivities. The products generated from this method have promising anticancer activities.

Automated summary

An organocatalyzed stereoselective domino reaction for the synthesis of multicyclic spirooxindole derivatives bearing two stereogenic quaternary carbon atoms is reported. The chiral thiourea catalyst with alkyl substitution efficiently tolerates a wide range of substrates, yielding spirooxindole derivatives with an O,O-acetal-fused tricyclic skeleton or tetrahydroxanthone moiety in moderate to good yields and excellent selectivities. The products generated from this method show promising anticancer activities.