title: 6-hydroxy-4-en-3-one sterols from the marine sponge Iotrochoto birotulata.
abstract: Five sterols with a nucleus skeleton of 6-hydroxy-4-en-3-one, namely cholesta-6beta-hydroxy-4-en-3-one (1), ergosta-6beta-hydroxy-4,24(28)-dien-3-one (2), ergosta-6alpha-hydroxy-4,24(28)-dien-3-one (3), ergosta-6alpha-hydroxy-4,22-E-dien-3-one (4), and ergosta-28-methyl-6beta-hydroxy-4,24(28)-dien-3-one (5) have been isolated from the marine sponge Iotrochoto birotulata, collected from the southern China sea. Sterols 2-4 are new compounds, and 1 has been isolated from marine organisms for the first time. The structures have been elucidated on the basis of extensive spectroscopic and chemical properties.
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China.
authors.forename: Li-Ya
authors.initials: LY
authors.lastname: Li
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Deng
authors.forename: Hong-Zheng
authors.initials: HZ
authors.lastname: Fu
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Wen-Han
authors.initials: WH
authors.lastname: Lin
authors.forename: Peter
authors.initials: P
authors.lastname: Proksch
mesh_terms: D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011161:Porifera / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013261:Sterols / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D013261:Sterols