title: Selaginellin A and B, two novel natural pigments isolated from Selaginella tamariscina.
abstract: Two new unusual natural pigments were first isolated from the whole herbs of Selaginella tamariscina. The structure of selaginellin A (1) was established as (R,S)-4-[(4'-hydroxy-3-((4-hydroxyphenyl)ethynyl)biphenyl-2-yl)(4-hydroxyphenyl)methylene]-2,5-cyclohexadien-1-one and selaginellin B (2) as (R,S)-4-[(4'-methoxy-4-(methyl)-3-((4-methoxyphenyl)ethynyl)biphenyl-2-yl)(4-methoxyphenyl)methylene]-2,5-cyclohexadien-1-one, along with four known biflavonoids, amentoflavone (3), hinokiflavone (4), heveaflavone (5), and 7''-O-methylamentoflavone (6). Their chemical structures were elucidated by spectral analysis of electrospray ionization mass spectroscopy (ESI-MS), one-dimensional nuclear magnetic resonance spectroscopy (1D-NMR) and two-dimensional-nuclear magnetic resonance spectroscopy (2D-NMR) including (1)H-NMR, (13)C-NMR, distortionless enhancement by polarization transfer (DEPT) and heteronuclear multiple bond coherence (HMBC), and single-crystal X-ray diffraction techniques.
authors.affiliation: Department of Chinese Materia Medica and Natural Products, National Institute for the Control of Pharmaceutical & Biological Products, Beijing, PR China.
authors.forename: Xian-Long
authors.initials: XL
authors.lastname: Cheng
authors.forename: Shuang-Cheng
authors.initials: SC
authors.lastname: Ma
authors.forename: Jian-Dong
authors.initials: JD
authors.lastname: Yu
authors.forename: Shi-Ying
authors.initials: SY
authors.lastname: Yang
authors.forename: Xin-Yue
authors.initials: XY
authors.lastname: Xiao
authors.forename: Jun-Ying
authors.initials: JY
authors.lastname: Hu
authors.forename: Yang
authors.initials: Y
authors.lastname: Lu
authors.forename: Pang-Chui
authors.initials: PC
authors.lastname: Shaw
authors.forename: Paul Pui-Hay
authors.initials: PP
authors.lastname: But
authors.forename: Rui-Chao
authors.initials: RC
authors.lastname: Lin
mesh_terms: D001713:Biphenyl Compounds / Q000737:chemistry / Q000302:isolation & purification*; D003512:Cyclohexanones / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D010860:Pigments, Biological / Q000737:chemistry / Q000302:isolation & purification*; D032503:Selaginellaceae / Q000737:chemistry*
chemical_list: C530550:(R,S)-4-((4'-hydroxy-3-((4-hydroxyphenyl)ethynyl)biphenyl-2-yl)(4-hydroxyphenyl)methylene)-2,5-cyclohexadien-1-one; C530549:(R,S)-4-((4'-methoxy-4-(methyl)-3-((4-methoxyphenyl)ethynyl)biphenyl-2-yl)(4-methoxyphenyl)methylene)-2,5-cyclohexadien-1-one,; D001713:Biphenyl Compounds; D003512:Cyclohexanones; D010860:Pigments, Biological