Patent ID: 7642370

Claim:
A method for preparing a prostaglandin derivative represented by the following general formula (I): wherein Ph represents phenyl group, R 1 represents a C 1-7 alkyl group, a C 1-7 alkenyl group, phenyl group, or benzyl group, which comprises: (1) converting a compound represented by the following formula (II), wherein X represents a protective group selected from the group consisting of an aroyl group having 0 to 3 substituents, a trialkylsilyl group, and a triarylsilyl group, wherein the substituents of the aroyl group are selected from the group consisting of a halogen atom, a C 1-6 alkyl group and a C 6-12 aryl group into a compound represented by the following formula (IV) by oxidizing the compound of the formula (II) into an aldehyde and then reacting the aldehyde with a phosphonic acid ester represented by the following formula (III) (R 2 represents a C 1-6 alkyl group or a C 6-12 aryl group); (2) converting the compound represented by the following formula (IV) into a compound represented by the following formula (V) by reducing the oxo group on the side chain of the compound of the formula (IV) using (S)-1,1′-binaphthyl-2-2′-dioxyaluminum hydride as a reducing agent; (3) converting the compound represented by the following formula (V) into a compound represented by the following formula (VI) by hydrogenating the compound of the formula (V); (4) converting the compound represented by the following formula (VI) into a compound represented by the following formula (VII) by removing the protective group X of the compound of the formula (VI); (5) converting the compound represented by the following formula (VII) into a compound represented by the following formula (VIII) by protecting the hydroxyl groups of the compound of the formula (VII) with protective groups P, wherein the protective group P is a tetrahydropyranyl group; (6) converting the compound represented by the following formula (VIII) into a compound represented by the following formula (IX) by reducing the oxo group on the lactone ring of the compound of the formula (VIII); (7) converting the compound represented by the following formula (IX) into a compound represented by the following formula (X) by reacting the compound of the formula (IX) with a 4-carboxybutyltriphenylphosphonium halide; and (8) converting the compound represented by the following formula (X) into a compound represented by the following formula (XI) by esterifying the carboxyl group of the compound of the formula (X) and then removing the protective groups P: (in the above formulas (III) to (XI), Ph represents phenyl group).