New ophiuroid-type steroids from the starfish pteraster tesselatus

Two new steroid sulfates have been isolated and a new minor steroid sulfate identified from the starfish Pteraster tesselatus. The structures of the new steroids were established on the basis of spectroscopic data as the 3,21-disulfate of (20R, 25R)-24-methyl-5alpha-cholest-24(28)-ene-2beta,3alpha,21,26-tetraol (1) and the 2,21-disulfate of (20R,25R,S)-cholest-5-ene-2beta,3alpha, 21,26-tetraol (2). The new minor steroid proved to be the 3, 21-disulfate of (20R,25R)-5alpha-cholestane-2beta,3alpha,21, 26-tetraol (3). All the compounds have structural features characteristic for ophiuroid-type steroids.