Mycaloside A, a new steroid oligoglycoside with an unprecedented structure from the Caribbean sponge Mycale laxissima

The structure of mycaloside A (1) isolated front the Caribbean sponge Mycale laxissima has been established as (22E,20R,24S)-3-O-{alpha-D-Gelp(1-->2)-beta-D-Arap(1-->3)-[beta-D-Gelp(1-->4)]-beta-D-Glep}-3beta,4beta,15alpha,21-tetrahydroxy-24-methylcholesta-5,22-diene by interpretation of spectral data and chemical transformations. (C) 2002 Elsevier Science Ltd. All rights reserved.