Identification of pentahydroxy bile alcohols in cerebrotendinous xanthomatosis: characterization of 5β-cholestane-3α, 7α, 12α, 24xi, 25-pentol and 5β-cholestane-3α, 7α, 12α, 23xi, 25-pentol

Abstract

This paper describes studies dealing with the nature of the C27 pentahydroxy bile alcohols present in the bile and feces of two patients with cerebrotendinous xanthomatosis (CTX). The presence of a bile alcohol having the structure 5β-cholestane-3α,7α,12α,24α,25-pentol was confirmed by separation of the two 24-hydroxy epimers of 5β-cholestane-3α,7α,12α,24,25-pentol and characterization of the dpimers by gas-liquid chromatography and infrared and mass spectrometry. Tentative assignment of the 24α and 24β configuration was made on the basis of molecular rotation differences. A second major bile alcohol excreted by the CTX subjects was 5β-cholestane-3α,7α,12α,23xi,25-pentol. Its structure was determined by infrared spectrometry, proton magnetic resonance spectrometry, and mass spectrometry because a reference compound was not available.