The stereoisomers of 3, 4-dihydroxy-6-methoxy-2, 2-dimethyl-chroman 3, 4, 7-trihydroxy-6- acetyl-2, 2-dimethyl-chroman were conveniently prepared for the first time via a synthesis in which Sharpless asymmetric dihydroxylation and Jacobsen's catalytic asymmetric epoxidation are the key steps.