PURPOSE: To simply obtain the subject compound useful as a synthetic intermediate for various physiologically active substances by asymmetrically dihydroxylating a meso-cis-dihydroxycyclohexadiene derivative, deprotecting a cyclic acetal of the prepared derivative.

CONSTITUTION: A meso-cis-1,2-dihydroxy-3,5-cyclohexadiene derivative of formula I (R1 and R2 are H, lower alkyl or aryl) is asymmetrically dihydroxylated to give an optically active 1,2,3,4-tetrahydroxy-5-cyclohexene derivative of formula II or formul-a III. A cyclic acetal of the derivative is deprotected to give an optically active 1,2,3,4-tetrahydroxy-5-cyclohexene (optically active conduritol) of formula IV of formula V. In the dihydroxylation, AD-mix-α or AD-mix βis preferably used as the oxidizing agent.