IMPROVED PROCESS FOR PREPARING ATORVASTATIN

A process for preparing atorvastatin as a therapeutic agent for hyperlipidemia is provided to simplify the preparation process by eliminating a specific function group-introducing process, improve preparation yield and purity by inhibiting production of by-products and performing the process under mild condition, and reduce the preparation time. A process for preparing atorvastatin represented by the formula(1) comprises the steps of: (i) performing N-alkylation reaction between 2-(4-fluorobenzene)-3-phenyl-4-carboaniline-5-isopropyl-pyrrol represented by the formula(2) with cis-t-butyl-7-halo-2-alkoxy-3,5-dioxane-heptanoate represented by the formula(3) to prepare 2-(4-fluorophenyl)-3-phenyl-4-carboaniline-5-isopropyl-1N(cis-t-butyl-2-alkoxy-3,5-dioxane-7-amido-heptanoate)pyrrole represented by the formula(4) wherein R is C1-C6 alkyl group and X is halogen atom; and deprotecting and hydrolyzing the compounds represented by the formula(4) in alcohol solvent in the presence of acid catalyst at 0-25 deg. C.