Abstract: An immobilized lipase is employed in an organic solvent to esterify diol lactone derivatives of HMG-CoA reductase inhibitors to form HMG-CoA reductase inhibitors of formula (I). ##STR1## This process allows for the efficient, one-step production of HMG-CoA reductase inhibitors of structural formula (I).

Abstract: Novel strains of Aspergillus terreus have been discovered which provide fermentation production of at least 5.2 g/L of 7-[1,2,6,7,8,8a(R)-hexahydro-2(S),6(R)-dimethyl-8(S)-hydroxy-1(S)-naphthyl ]-3(R),5(R)-dihydroxyheptanoic acid (triol acid, I), but with production of not more than 0.85 g/L of (triol acid)-related side products and specifically less than 0.10 mg/liter of lovastatin. The predominant fermentation product triol acid, may be converted in a straightforward manner to its lactone form, in which it is an inhibitor of HMG-CoA reductase and thus useful as an antihypercholesterolemic agent, and in which it may also serve as an intermediate for preparation of other HMG-CoA reductase inhibitors.

Abstract: Biosynthetic production of 7-[1',2',6',-7',8',8a'(R)-hexahydro-2'(S),6'(R)-dimethyl-8'(S)-hydroxy-1'( S)-naphthyl]-3(R),5(R)-dihydroxyheptanoic acid, "triol acid", is accomplished by enzymatic hydrolysis of lovastatin acid or a salt thereof, by treating it with Clonostachys compactiuscula ATCC 38009 or ATCC 74178, or mutants thereof, or a cell-free extract derived therefrom, or a hydrolase derived therefrom. The triol acid and its lactone form are both inhibitors of HMG-CoA reductase and thus useful as anti-hypercholesterolemic agents, and may also serve as intermediates for preparation of other HMG-CoA reductase inhibitors. Also, in the synthesis of simvastatin by direct methylation of lovastatin, selective hydrolysis of residual lovastatin salt by treatment with Clonostachys compactiuscula ATCC 38009 or ATCC 74178 or mutants thereof or a cell-free extract derived therefrom, or a hydrolase derived therefrom yields the "triol" salt which can be easily separated from simvastatin.