Synthesis and purity assessment of tetra- and pentaacyl lipid A of Chlamydia containing (R)-3-hydroxyicosanoic acid
作者:Alla Zamyatina、Harald Sekljic、Helmut Brade、Paul Kosma
DOI:10.1016/j.tet.2004.10.017
日期:2004.12
Based on structural data of lipid A from Chlamydia trachomatis strains, chemically pure tetra- and pentaacyl 1,4'-bisphosphoryl as well as the related 4'-monophosphoryl derivatives of lipid A were synthesized. (R)-3-Hydroxyicosanoic acid as a chiral constituent was prepared via Noyori-reduction of methyl-3-oxoicosanoic acid. Synthetic intermediates were O-acylated with myristoic acid residues at positions 3 and 3' and N-acylated with (R)-3-hydroxyicosanoic acid at both glucosamine units. Efficient purification methods for highly hydrophobic long-chain tri-, tetra- and pentaacyl progenitors of lipid A have been developed. Purity and homogeneity of the synthetic target compounds were confirmed by NMR and MS-data as well as a sensitive immunostaining approach. The tetra- and pentaacyl species serve as biomedical probes to investigate the endotoxic potential of chlamydial lipid A and to clarify its role in Chlamydia associated infections. (C) 2004 Elsevier Ltd. All rights reserved.