New sulfated polyhydroxysteroids from the Antarctic ophiuroid Astrotoma agassizii

Three new and two known sulfated steroidal polyols have been isolated from the Antarctic ophiuroid Astrotoma agassizii. All of the new steroids possess a terminal isopropenyl group and a C-21 sulfoxy moiety in the side chain but differ in the steroidal nuclei. The structures of these new steroids were established from spectral and chemical correlations with related steroids as (20R)-cholesta-5,24-diene-2 beta,3 alpha,21-triol 2,21-disulfate (1), (20R)-5 alpha-cholest-24-ene-2 beta,3 alpha,21-triol 3,21-disulfate (3), and (20R)-cholesta-5,24-diene-2 alpha,3 alpha,4 beta,21-tetrol 3,21-disulfate (5). Analysis of the nonsulfated sterol fraction has shown the presence of cholest-5-en-3 beta-ol, cholesta-5,24-dien-3 beta-ol and (22E) cholesta-5,22-dien-3 beta-ol as the major sterols.