OPTICALLY ACTIVE SUBSTITUTED HYDROXY TRICYCLIC LACTONE DERIVATIVE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To enable easy preparation of the subject compound which is useful as a synthetic intermediate for a camptothecin derivative by optical resolution of an RS type substituted hydroxy tricyclic lactone derivative having an optically active substituent introduced to the OH in its molecule. SOLUTION: An RS type compound which is represented by formula I R<0> is a residue of an optically active amino acid after an OH is removed from one carboxyl group in the molecule in which the amino or imino or carboxyl group in the residue is protected [for example, a residue after removal of OH of carboxyl from a compound of formula II (Z is an imino-protecting group; X, Y are each H or incorporated together to form a ring in this case, the dotted line denotes a double bond; (n) is 0, 1; * is an absolute configuration of R or S)]}, or its acetal is optically dissolved by fractional crystallization or chromatography to obtain an optically active compound of formula III.