Mevinolinic Acid, Monoammonium Salt can be used as reactant/reagent in process for the preparation of the Simvastatin precursor, 2,2-dimethylbutanoic acid (1S,3R,7S,8S,8aR)-8-[(3R,5R)-7-(cyclopropylamino)-3,5-dihydroxy-7-oxoheptyl]-1,2,3,7,8,8a-hexahydro-3,7-dimethyl-1-naphthalenyl ester, via an amidation reaction.
