Cinchona alkaloids exist in nature as pseudoenantiomers, which allow Cinchona alkaloid-catalyzed reactions to provide high enantioselectivities and yields toward both enantiomers of interest in many reactions. The pseudoenantiomers like Quinine and Quinidine are diastereomers with the same stereochemical configuration at C3 and C4, but opposite configuration at C8 and C9. Used as a chiral ligand or catalyst these versatile tools provide access to the R- or S-isomer of the target molecule. In catalytic reactions the configuration of the stereo centers C8 and C9 is high relevance.

The use of pseudoenantiomers is a well-known method of achieving products of complementary stereochemistry.