6(R)-(2-(8'-acyloxy-2'-methyl-6'-methyl (or hydrogen)-polyhydronaphthyl-1')-ethyl)-4(R)-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-ones, the hydroxy acid form of said pyranones, the pharmaceutically acceptable salts of said hydroxy acids, and the lower alkyl, and phenyl, dimethylamino or acetylamino substituted lower alkyl esters of said hydroxy acid, processes for preparing the same, and a pharmaceutical antihypercholesterolemic composition containing the same

Claim 1

A process for the preparation of a compound of structural formula: wherein R' is H or CH 3 ; R is (1) C 1-10 straight or branched chain alkyl except 2-(S)-butyl, ( 2 ) C 3-10 cycloalkyl, ( 3 ) C 2-10 alkenyl, ( 4 ) C 1-10 CF 3 -substituted alkyl, (5) phenyl, (6) halophenyl, (7) phenyl-C 1-3 alkyl, (8) substituted phenyl-C 1-3 alkyl in which the substituent is halo, C1-3 alkyl or C 1-3 alkox y ; the dotted lines at X, Y and Z represent possible double bonds, said double bonds, when any are present, being either X and Z in combination or X, Y or Z alone; and the corresponding dihydroxy acids of the formula: or a pharmaceutically acceptable salt of said acids, a C l-4 alkyl ester of said acids or a phenyl-, dimethylamino-, or acetylamino-substituted-C 1-4 alkyl esters of said acids, which comprises 1) heating a compound of formula: with an alkali metal hydroxide in a protic solvent followed by acidification and lactonization to give compound IV a-e ; ; 2) reacting the compound of the structure: with t-butyldimethylchlorosilane under an inert atmosphere at ambient temperature in the presence of an acid acceptor; 3) acylating the resulting 4-t-butyl- dimethylsilyloxy compound by: a) stirring it in solution with an acid chloride, RCOC1, in pyridine in an inert atmosphere in the presence of an acylation catalyst, or b) stirring it in solution at ambient temperature with an acid, RCOOH, and N,N-dicyclohexylcarbodiimide in the presence of an acylation catalyst, and 4) removing the silyl group by stirring at ambient temperature in tetrahydrofuran in the presence of 3 equivalents of tetrabutylammonium fluoride and 4 equivalents of acetic acid per equivalent of silyl compound. and, if desired, treating the resulting compound I a-e with abase, if desired, followed by careful acidification with dilute acid, or, if desired , treating the resulting compound I a-e with a C 1-4 -alkanol or with a phenyl-, dimethyl-amino-, or acetylamino C 1-4 alkanol.