合成路线1

An efficient synthesis of the optically active compound has been reported. Acid hydrolysis of the chiral acetonide (I) gave dihydroxy ester (II), which was selectively protected at the primary hydroxyl group as the O-trityl derivative (III). The beta-keto thioester (V) was obtained by condensation of palmitic acid (IV) with the magnesium salt of [(tert-butylthio)carbonyl]acetic acid via activation with carbonyl diimidazole. Silver salt-promoted condensation of thioester (V) with hydroxy ester (III) gave adduct (VI). The 3-acyltetronic acid system (VII) was obtained by cyclization of (VI) in the presence of tetrabutylammonium fluoride. Finally, deprotection of the trityl group using 1 N HCl afforded the title compound.