Novel Cholic-Acid-Type Sterones of Deltocyathus magnificus, a Deep- Water Scleractinian Coral from the Loyalty Islands, SW Pacific.

Cholic-acid-type 3-keto steroids 1–8, all isolated from Deltocyathus magnificus (2–8 after CH2N2 treatment), are the first secondary metabolites obtained from a deep-water scleractinian. Steroids 1–3, 5, and 7 are new, their main structural oddities being loss of C(24) (see 5) or hydroxylation in the side chain (see 3 and 7). Steroids 4, 6, and 8, from the same coral, were previously known from other marine organisms.