for the following products
2,2-Dimethyl-butanoic acid [1s-[1a,3a,4aa,7,8(2S*,4S*),8a]]-8-[2-[4-[[(1,1-dimethylethyl)dimethylsilyl]oxy]tetrahydro-6-oxo-2H-pyran-2-yl]ethyl]-1,2,3,4,4a,7,8,8a-octahydro-4a-hydroxy-3,7-dimethyl-1-n and 4-tert-Butyldimethylsilyl-4a'-hydroxy simvastatin
