The method of preparing high purity pitavastatin calcium statin

The present invention particularly relates to a method for preparing high purity pitavastatin calcium statin. Comprising the step of: (1) PI-9 hydrolysis to give (E) -7- [2- cyclopropyl-4- (4-fluorophenyl) -3-quinolyl] -3,5-dihydroxy -6 - heptenoic acid ⅰ; (2) ⅰ in the reaction medium, under the action of lipase, the reaction with the vinyl acetate separation to give (3R, 5S, E) -7- [2- cyclopropyl-4- (4-fluorophenyl) -3-quinolyl] -3,5-acetoxy-6-heptenoic acid II; (3) II hydrolyzed to give (3R, 5S, E) -7- [2- cyclopropyl-4- (4-fluorophenyl) -3-quinolyl] -3,5-dihydroxy-6-heptenoic acid IV; (4) IV reacted with CaCl2 pitavastatin calcium; present invention high ee values ​​obtained monomers, obtained pitavastatin calcium of high purity and high yield.