An undecaprenyl phosphate analog containing the phenoxy group at the ω-end of the oligoisoprene chain

A simple method for the preparation of a biologically active analog of bacterial undecaprenyl phosphate bearing the phenoxy group at the ω-end of the chain was developed on the basis of accessible polyprenols from mulberry (Morus nigra) leaves. It includes the selective van Tamelen epoxidation of the ω-terminal isoprene unit of polyprenyl acetates, conversion of the epoxides into ω-terminal aldehydes, their hydride reduction into hydroxy acetates followed by the Mitsunobu condensation with phenol, and phosphorylation of the resulting phenoxy alcohols. The biological activity of the obtained phosphates was tested by the radiometry method in the initiation of O-antigenic polysaccharide assembly reaction using the cell membrane preparations from the Gram-negative bacteria Salmonella arizona O:59 and Aeromonas hydrophila AH-1.