Method for preparing palbociclib

Abstract

This invention reveals the method for preparing Palbociclib (I). The preparation includes: produce the 6-acetyl-5-methyl-2-substituent-pyrido[2,3-d]pyrimidin-7(8H)-one (IV) through the ring-closure reaction by using accessible raw materials of 1-(4-amino-2-substituent-5-pyrimidinyl) ethanone (II) and acetylacetic ester (III); produce the 6-acetyl-8-cyclopentyl-5-methyl-2-substituent-pyrido[2,3-d]pyrimidin-7(8H)-one (VI) through the substitution reaction between the intermediate (IV) and the cyclopentane halide (V); prepare the Palbociclib (I) through the condensation and hydrolysis reactions between the intermediate (VI) and 4-(6-amino-3-pyridinyl)-1-piperazinecarboxylic acid 1,1-dimethylethyl ester (VII). This method for preparing Palbociclib (I) is characterized by easily available raw materials, concise process and economy and environmental protection, and it is suitable for industrialized production.

Dependencies are inferred from the claim text.