Structure Elucidation of Four Steroids From the Soft Coral Sinularia Nanolobata

Abstract

Four steroids namely 3β-hydroxyergosta-5,24(28)-diene-7-one (1), dissesterol (2), 16αhydroxysarcosterol (3), and sarcophytosterol (4) were isolated from the soft coral Sinularia nanolobata using various chromatographic methods. Their structures were elucidated by detailed analysis of the 1D and 2D NMR data and comparison with the reported values.

Chemical Diversity of Soft Coral Steroids and Their Pharmacological Activities

“…Thus, a series of steroids (20)(21)(22)(23)(24)(25) was isolated from the methanolic extract and their structures were established as: 5α,8α-epidioxygorgosta-6-en-3β-ol (20), 5α,8α-epidioxygorgosta-6,9(11)-dien-3β-ol (23), 22α,28-epidioxycholesta-5,23(E)-dien-3β-ol (25A), its C-22 epimer (25B) and compound (24) [64]. S. nanolobata yielded a sterol, sarcophytosterol (26), along with steroids (3) and ( 6) [65]. An unusual steroid, 3-(1 ,2 -ethandiol)-cholest-3β,5α,6α,11α-tetraol (27) and secosteroid (28) were isolated from the South China sea gorgonian S. suberosa [66].…”

“…The 17β, 20β-epoxy-23,24-dimethylcholest-5-ene-3β, 22-diacetate (59) and three unusual steroids (60)(61)(62) including secosteroid (62) were isolated from the Indian Ocean soft coral Sarcophyton crassocaula [93]. Cytotoxic steroids (63)(64)(65)(66)(67) were obtained from the acetone and MeOH extract of the soft coral Nephthea erecta [94]. A steroid with a spiro-ring A, B system named chabrolosteroid C (66) and chabrolosteroid A (68) were isolated from an organic extract of a Taiwanese soft coral Nephthea chabrolii [95].…”