NEW METHOD FOR PRODUCING NEPLANOCIN A AND INTERMEDIATE FOR THAT PURPOSE

PROBLEM TO BE SOLVED: To obtain Neplanocin A having strong carcinostatic action in a good yield by the short production process of reverse Diels-Alder reactions of an intermediate obtained from cyclopentadiene and 1,4-benzoquinone. SOLUTION: Neplanocin A is obtained by reacting a compound of formula I (R and R are each H or a 2-20C alkanoyl) as a starting raw material with a halogenation agent, by protecting the hydroxyl group of the resultant product, by treating it with an oxidizing agent, by reacting the product with an acetalizing agent, by dehalogenation to obtain a compound of formula II (Y is a protecting group), by the reverse Diels-Alder reaction of the compound of formula II, by treating the resultant product with an oxidizing agent or the like, by O. Mitsunobu synthesis of the product and by deblocking. For example, the compound of formula I is new and is obtained by the transesterification of a racemate of formula III with an acylating agent in the presence of a hydrolase. Not only compound of formula II but also other intermediates in the above reaction are all new.