Patent ID: 7671216

Claim:
A method for the preparation of (3R,5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-[(4-hydroxy methyl phenyl amino) carbonyl]-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid hemi calcium salt of Formula I, comprising: (a) reacting an amine of Formula II with methyl isobutyryl acetate of Formula III to form a compound of Formula of IV, wherein R is a hydroxy protecting group selected from the group consisting of acetyl, benzoyl, tetrahydropyranyl, methoxy methyl, methoxy ethoxymethyl, and benzyl; b) reacting the compound of Formula IV with benzaldehyde to form a compound of Formula V; c) reacting the compound of Formula V with 4-fluorobenzaldehyde to form a compound of Formula VI; d) reacting the compound of Formula VI with a compound of Formula VII to form a compound of Formula VIII; e) subjecting the compound of Formula VIII with a mineral acide simultaneously to induce acid-catalyzed cleavage of ketal and the hydroxy protecting groups to form a crude compound of Formula IX; f) purifying the crude compound of Formula IX to form a purified compound of Formula IX; g) subjecting the purified compound of Formula IX with a base to induce base-catalyzed hydrolysis to form a compound of Formula X; and h) reacting the compound of Formula X with aqueous solution of calcium acetate to form a compound of Formula I.