Synthesis of saturated, unsaturated, spin-labeled, and fluorescent cholesteryl esters: Acylation of cholesterol using fatty acid anhydride and 4-pyrrolidinopyridine.

A rapid, high yield method for the preparation of cholesteryl esters is described. The method is a modification of the catalytic procedure previously applied to the acylation of sn-glycero-3-phosphoryl-choline (Patel, K.M., J.D. Morrisett, and J.T. Sparrow, J. Lipid Res., 20:676 (1979). Cholesteryl esters are formed in excellent yield by acylating cholesterol with fatty acid anhydride or fatty acid and dicyclohexylcarbodiimide in methylene chloride containing 4-pyrrolidinopyridine. The versatility of the method is demonstrated by the preparation of the cholesteryl esters of saturated, unsaturated, spinlabeled, and labile fluorescent fatty acids.