Abstract
An efficient method for the synthesis of the natural product (+)-(R)-butyl ester of rosmarinic acid (+)-(R)-1 and its enantiomer ( − )-(S)-1 has been developed by chemical resolution of its phenyl lactic acid precursors 4 with ( − )-menthol. Their antioxidative and anti-tumor activities were evaluated.
Acknowledgements
We wish to thank Dr. Hong-qi Xin and Professor Geng-tao Liu for in vitro testing.