Of mevinic acid

Using water as the solvent enhanced the rate of the hetero-Diels-Alder reaction relative to the dimerization of cyclopentadiene. In addition, the reaction is much faster at a low pH, which implies that the reaction is acid catalyzed. The 5,5-fused system generated has been used in the total synthesis of several bioactive compounds, including the anti-HIV agent (—)-carbovir (Eq. 12.51)121 and the hydroxylactone moiety of mevinic acids (Eq. 12.52).122... 

P. Boquel, C. Loustau Cazalet, Y. Chapleur, S. Samreth, and F. Bellamy, An expeditious enantiospecific synthesis of a precursor of the lactonic portion of mevinic acids, Tetrahedron Lett. 33 1997 (1992). 

Y. Chapleur, The chemistry and total synthesis of mevinic acids, in Recent Progress in the Chemistry of Antibiotics, G. Lukacs and S. Ueno, eds., Springer, New York, 1993 pp. 829-937. 

Rhabdomyolysis in a stable renal transplant recipient was attributed to the presence of red yeast rice (Monascus purpureus) in a herbal mixture (116). The condition resolved when he stopped taking the product. Rice fermented with red yeast contains several types of mevinic acids, including monacolin-K, which is identical to lovas-tatin. The authors postulated that the interaction of ciclosporin with these compounds through cytochrome P450 had resulted in the adverse effect. Transplant recipients must be cautioned against using herbal products to lower their lipid concentrations, in order to prevent such complications. 

Lactone ring expansion.1 The 7-lactone 2 can be expanded to the protected y-lactol 4, characteristic of mevinic acids, by reaction of the lactol of 2 with this Wittig reagent to provide a vinyl sulfide 3. Conversion of the vinyl sulfide to 4 was... 

Boquel, P, Chapleur, Y, A new strategy for the synthesis of mevinic acids analogues. Tetrahedron Lett, 31, 1369-1372, 1990. 

A review on the synthesis of mevinic acids such as compactin (1)... 

Roberts et al. [48] have used the other diol enantiopode 155, derived from (+)-150, to construct the hydroxylactone moiety (156) of mevinic acids such as compactin and mevinolin ... 

A review of syntheses of the Prelog-Djerassi lactonic acid includes carbohydrate-based routes,27 and there have been two further reports of syntheses of the P-hydroxy-5-lactone unit (38) of mevinic acid and its congeners.28, 29 jn a synthesis of the mosquito oviposition pheromone (39), the chiral centres were derived from those of 2,3-0-ethylidene-D-erythrose, with this chiron being extended by Wittig reactions, in a similar manner to the use of 2-deoxy-D-ribose in an earlier approach to the same target (S.-K. Kang and I.-H. Cho, Tetrahedron Lett., 1989, 30, 743). 

The 3,4-epoxide (35), obtained from triacetyl-D-glucal, has been used to prepare the dideoxyhexose derivative (36) leading to the analogues (37) of mevinic acids (enzyme inhibitors)(Scheme 11) ... 

Scheme 15 Synthesis of the p-hydroxy-6-lactone framework of mevinic acid...

Shimizu et al. have reported the synthesis of the 4-hydroxy-6-lactone component of mevinic acid by lactonization of a 6-hydroxy ester [53] (Scheme 16). Reaction of lithio-fcrt-butylacetate with p-trichloromethyl-p-lactone 80 gave 6-hydroxy-p-keto ester 81. A stereoselective syn reduction of the ketone, lactcmization, and protection of the secOTidaiy alcohol provided the lactone. The trichloromethyl group was reduced with tri- -butyltin hydride to furnish 6-chloromethyl lactone intermediate 84. 

Kumar and Dittmer have reported the synthesis of intermediates for the lactone moiety of mevinic acids using tellurium-induced nucleophilic reduction developed by their own group as the key step [122] (Scheme 75). Alcohol 331 was protected and converted into aldehyde 332, which upon Wittig reaction and reduction gave allylic alcohol 333. Sharpless epoxidation of 333 and tosylation of the primary alcohol afforded tosylate 334, which underwent the tellurium-induced transposition providing lactone 335 through spontaneous lactonization. However, in the case of the corresponding fcrf-butyl ester, there was no spontaneous lactonization observed. 

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