Axiceramide A and B, Two Novel tri‐α‐Glycosylceramides from the Marine Sponge Axinella sp.

Two new glycosphingolipids, axiceramide A (1a) and B (2a), have been isolated as their peracetates (1b and 2b, respectively) from the marine sponge Axinella sp., and their structures elucidated by spectroscopic and chemical analysis. Axiceramide A and B, both composed of a complex mixture of homologues, are the first example of natural triglycosylceramides with three hexopyranose units all engaged in α-glycosidic linkages.