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Journal ArticleDOI

Bibenzyl derivatives from the orchid Bulbophyllum protractum

01 Jan 1997-Phytochemistry (Pergamon)-Vol. 44, Iss: 1, pp 167-172
TL;DR: In this paper, two new bibenzyl derivatives were isolated from the orchid Bulbophyllum protractum and designated bulbophyllin and bulbophilusidin.
About: This article is published in Phytochemistry.The article was published on 1997-01-01. It has received 31 citations till now. The article focuses on the topics: Bibenzyl.
Citations
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Journal ArticleDOI
TL;DR: Six newphenanthrene derivatives, including three monophenanthrenes (1-3), two biphenanholdes (4 and 5), and a triphenanthrene (6), have been isolated from an ethanolic extract of the tubers of Cremastra appendiculata.
Abstract: Six newphenanthrene derivatives, including three monophenanthrenes (1-3), two biphenanthrenes (4 and 5), and a triphenanthrene (6), have been isolated from an ethanolic extract of the tubers of Cremastra appendiculata. Using spectroscopic methods, the structures of compounds 1-6 were determined as 1-hydroxy-4,7-dimethoxy-1-(2-oxopropyl)-1H-phenanthren-2-one (1), 1,7-dihydroxy-4-methoxy-1-(2-oxopropyl)-1H-phenanthren-2-one (2), 2-hydroxy-4,7-dimethoxyphenanthrene (3), 2,7,2'-trihydroxy-4,4',7'-trimethoxy-1,1'-biphenanthrene (4), 2,2'-dihydroxy-4,7,4',7'-tetramethoxy-1,1'-biphenanthrene (5), and 2,7,2',7',2' '-pentahydroxy-4,4',4' ',7' '-tetramethoxy-1,8,1',1' '-triphenanthrene (6), respectively. Compounds 1-6 and two known compounds, cirrhopetalanthin (7) and flavanthrinin (8), obtained previously from this plant, were evaluated against six human cancer cells and a normal cell line.

77 citations

Book ChapterDOI
TL;DR: Stilbenoids are formed by a particular branch of the flavonoid biosynthetic pathway and are of special interest to natural product researchers for their roles in plant resistance to fungal pathogens and their biological effects as discussed by the authors.
Abstract: Stilbenoids are formed by a particular branch of the flavonoid biosynthetic pathway. They are of special interest to natural product researchers for their roles in plant resistance to fungal pathogens and their biological effects. This review in the volume of Bioactive Natural Products provides a comprehensive account of the occurrence, chemistry, biological roles and activities of the stilbenoids. Nearly 800 stilbenoids, isolated from natural sources in the recent 12 years, are grouped into structural types and discussed in terms of their reported pharmacological activity. The major groups of stilbenoids which are discussed in detail include stilbenes, bibenzyls, bisbibenzyls, phenanthrenoids, stilbene oligomers etc. Detailed tables and figures list the occurrence of stilbenoids in major plant species, and methods used for extracting and analyzing stilbenoids are discussed. Biosynthetic pathways and chemical synthesis are reviewed and the biological activities of stilbenoids are also addressed. The coverage of the new structures is from 1994 to 2006.

75 citations

Journal ArticleDOI
TL;DR: A new enantiomeric pair of spirodiketones, (+)- and (-)-denobilone A (1 and 2), three new phenanthrene derivatives (3-5), and three new biphenanthrenes (22-24), along with 11 known phenanthene derivatives (6-16), five known bibenzyl derivatives (17-21), and four known biphenAnthrenes
Abstract: A new enantiomeric pair of spirodiketones, (+)- and (-)-denobilone A (1 and 2), three new phenanthrene derivatives (3-5), and three new biphenanthrenes (22-24), along with 11 known phenanthrene derivatives (6-16), five known bibenzyl derivatives (17-21), and four known biphenanthrenes (25-28), were isolated from Dendrobium nobile. The structures of 1-5 and 22-24 were elucidated using comprehensive spectroscopic methods. (+)-Denobilone and (-)-denobilone A (1 and 2) were isolated as a pair of enantiomers by chiral HPLC. The absolute configurations of (+)- and (-)-denobilone A (1 and 2) were determined by comparing their experimental and calculated electronic circular dichroism spectra. The absolute configuration of denobilone B (3) was determined by X-ray crystallographic analysis. The inhibitory activities of all compounds against nine phytopathogenic fungi and three cancer cell lines were evaluated.

72 citations

Journal ArticleDOI
TL;DR: Two new phenanthrenes (4-methoxyphenanthrene-2,3,7-triol and 4-methyltetrol) and two new 9,10-dihydrophenthrenes were discovered in this paper.

66 citations

References
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Journal ArticleDOI
TL;DR: All the bibenzyls caused leukemia cells to accumulate in mitosis at cytotoxic drug concentrations; however, a wide range of in vitro activity against the protein tubulin (the major component of the mitotic spindle) was observed.
Abstract: Further investigation of a CH2Cl2 fraction prepared from the South African tree Combretum caffrum for substances inhibitory to the murine P-388 lymphocytic leukemia (PS system) cell line has led to the isolation of two new bibenzyls, designated combretastatins B-3 and B-4, accompanied by the previously known bibenzyls 7, 8, and 9. The structure of each substance was ascertained by results of mass and nmr spectral analyses and confirmed by crystal structure determination (for 7) or synthesis. Combretastatins B-3 and B-4 gave PS ED50 values of 0.4 and 1.7 micrograms/ml, respectively, and bibenzyls 7, 8, and 9 were comparably cell growth inhibitory against the PS cell line with ED50 results of 1.7, 2.5, and 0.25 ug/ml, respectively. All the bibenzyls caused leukemia cells to accumulate in mitosis at cytotoxic drug concentrations; however, a wide range of in vitro activity against the protein tubulin (the major component of the mitotic spindle) was observed.

79 citations

Journal ArticleDOI
TL;DR: 2,7-Dihydroxy-4-methoxy-9,10-dihydrophenanthrene was isolated and identified from the whole plant of Coelogyne ochracea and C. elata.

77 citations

Journal ArticleDOI
TL;DR: Three new substituted bibenzyls (1,2-diarylethanes) aloifol I and aloIFol II and a new substituted 9,10-dihydrophenanthrene, 6-O-methylcoelonin in addition to batatasin III, coel onin and gigantol have been isolated and characterized.

70 citations

Journal ArticleDOI
TL;DR: Lusianthrin and lusian-thridin, two new stilbenoids, were isolated from the orchid Lusia indivisa.

66 citations

Journal ArticleDOI
TL;DR: Flavanthrin, the first dimeric 9,10-dihydrophenanthrene derivative, was isolated from the orchid Eria flava which also yielded the previously reported 9, 10-dibhrenanthrene coelonin this paper.

54 citations