Synthesis of the mannosyl erythritol lipid MEL A; confirmation of the configuration of the meso-erythritol moiety

The total synthesis of the two possible diastereomers of mannosylerythritol lipid A, a novel biosurfactant from Candida antartica T-34 with promising anti-proliferative properties in several cell lines, is described. By comparison with an authentic sample, the natural material is confirmed as a single diastereomer with the 4-O-(β-d-mannopyranosyl) d-erythritol configuration.