| abstract |
Atorvastatin calcium, the substance known by the chemical name [(R-(R*,R*)]-2-(4-fluorophenyl)-b,ddihydorxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid hemi calcium salt is known as HMG-CoA reductase inhibitor and is used as an antihypercholesterolemic agent. Atorvastatin is usually prepared as its calcium salt since it enable atorvastatin to be conveniently formulated in the pharmaceutical formulations, for example, in tablets, capsules, powders and the like for oral administration. Atorvastatin calcium can exist in an amorphous form or in one of the crystalline forms (Form I, Form II, Form III and Form IV). Atorvastating calcium is the substance which is very slightly water-soluble, and it has been found that the crystalline forms are less readily soluble than the amorphous form which may cause problems in the bioavailability of atorvastatin in the body. The present invention relates to a novel process for converting the intermediate in the synthesis of atorvastatin having the following formula (I) or atorvastatin lactose into the non-crystalline atorvastatin calcium: wherein A denotes a common protection group or separate protection groups for the dihydroxy group and B denotes a carboxylic acid protection group. |