New acyclic analogues of lipid A: synthesis of 4-phosphonoxybutyl and 3-phosphonoxypropyl glycosides of 2-amino-2-deoxy-D-glucose.

Several analogues of lipid A have been synthesized, in which the reducing monosaccharide moiety of the parent molecule has been replaced by an acyclic spacer. The new compounds show high endotoxic activity and are able to protect neutropenic mice against pseudomonas infection, two properties characteristic of LPS-like molecules.