title: New hemiketal steroid from the soft coral Cladiella sp.
abstract: [structure: see text] A new hemiketal steroid, named cladiellin A (1), was first isolated from the soft coral Cladiella sp. Its structure was determined by spectroscopic methods and X-ray analysis. Compound 1 easily converted to 1a when NMR spectra were measured in CDCl(3) solution and quickly changed to 1b when pyridine was used. The structures of dehydrated products 1a and 1b were determined by spectroscopic analysis. Bioassay showed that all these three compounds showed antioxidant activity.
authors.affiliation: School of Chemistry and Chemical Engineering, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, China.
authors.forename: Guang-Wen
authors.initials: GW
authors.lastname: Zhang
authors.forename: Xiang-Quan
authors.initials: XQ
authors.lastname: Ma
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kurihara
authors.forename: Cui-Xian
authors.initials: CX
authors.lastname: Zhang
authors.forename: Xin-Sheng
authors.initials: XS
authors.lastname: Yao
authors.forename: Jing-Yu
authors.initials: JY
authors.lastname: Su
authors.forename: Long-Mei
authors.initials: LM
authors.lastname: Zeng
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D013256:Steroids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D013256:Steroids; C506145:cladiellin A