Topic
Gymnopusin
About: Gymnopusin is a research topic. Over the lifetime, 9 publications have been published within this topic receiving 158 citations. The topic is also known as: gymnopusin.
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TL;DR: In this paper, Reptanthrin and isoreptanthrin, two new dimeric phenanthrenes, were isolated from the orchid Bulbophyllum reptans which also afforded nine known stilbenoids, viz.
Abstract: Reptanthrin and isoreptanthrin, two new dimeric phenanthrenes, were isolated from the orchid Bulbophyllum reptans which also afforded nine known stilbenoids, viz. gymnopusin ( 1a ) [2,7-dihydroxy-3,4,9-trimethoxyphenanthrene], confusarin ( 1c ) [2,7-dihydroxy-3,4,8-trimethoxyphenanthrene], 2,7-dihydroxy-3,4,6-trimethoxyphenanthrene ( 1d ) and its 9,10-dihydro derivative, flavanthrinin ( 1e ) [2,7-dihydroxy-4-methoxyphenanthrene] and its 9,10-dihydro derivative (coelonin), 3,3′-dihydroxy-5-methoxybibenzyl (batatasin-III), cirrhopetalanthrin ( 2a ) [2,2′,7,7′-tetrahydroxy-4,4′-dimethoxy-1,1′-biphenanthryl] and its 9,9′,10,10′-tetrahydro derivative ( flavanthrin). The structures of reptanthrin and isoreptanthrin were established as 2,2′,7,7′-tetrahydroxy-3,3′,4,4′,9,9′-hexamethoxy-1,1′-biphenanthryl ( 2c ) and 2,2′,7,7′-tetrahydroxy-3,3′,4,4′,9,9′-hexamethoxy-1,8′-biphenanthryl ( 3a ), respectively, from spectral and chemical evidence including their biomimetic synthesis from the congener 1a with phosphomolybdic acid (PMA) on silica gel.
41 citations
TL;DR: The results suggested that the relaxant activity of the products does not involve a direct nitrergic or antihistaminergic mode of action or an interference with calcium influx into the smooth muscle cells.
Abstract: 2,5-Dihydroxy-3,4-dimethoxyphenanthrene (1), fimbriol-A (2), nudol (3), gymnopusin (4) and erianthridin (5) isolated from Maxillaria densa provoked a concentration-dependent inhibition of the spontaneous contractions of the rat ileum with potencies comparable to papaverine. In order to establish the mode of action of stilbenoids 1–5, their effect on the contractions induced by different spasmogens (histamine, barium chloride and l -NAME) was investigated. In general, the results suggested that the relaxant activity of the products does not involve a direct nitrergic or antihistaminergic mode of action or an interference with calcium influx into the smooth muscle cells.
34 citations
TL;DR: Gymnopusin, the first naturally occurring phenanthrene derivative having a hydroxyl group at C-9, was isolated from the orchid Bulbophyllum gymnopus.
Abstract: Gymnopusin, the first naturally occurring phenanthrene derivative having a hydroxyl group at C-9, was isolated from the orchid Bulbophyllum gymnopus . It was shown to be 7,9-dihydroxy-2,3,4-trimethoxyphenanthrene ( 1a ) mainly from the spectral data of the compound and those of its diacetyl ( 1b ) and dimethyl ether ( 1c ) derivatives.
32 citations
TL;DR: The functional results obtained suggest that 1 induces relaxation through an endothelium-independent pathway by the control of cationic channels (calcium channel blockade and potassium channel opening) in the myogenic response of rat aortic rings.
Abstract: The phenanthrenes gymnopusin (1), fimbriol A (2), and erianthridin (3) from Maxillaria densa were found to induce significant relaxant effects in a concentration-dependent and endothelium-independe...
21 citations
TL;DR: Both phenanthrene derivatives exhibited moderate cytotoxicity to all mammalian cells tested, which precludes their use as a bioherbicide.
Abstract: Two phenanthrene derivatives, characterized as erianthridin (9,10-dihydro-2,7-dihydroxy-3,4-dimethoxyphenanthrene) and gymnopusin (2,7-dihydroxy-3,4,9-trimethoxyphenanthrene), were isolated from an extract of the orchid Maxillaria densa, using phytotoxicity with amaranth (Amaranthus hypochondriacus) to guide fractionation. Gymnopusin and erianthridin inhibited radicle elongation of A. hypochondriacus seedlings with IC50 values of 330 and 58.2 μM, respectively. The phytoxicity of the two phenanthrene derivatives was also assessed on duckweed (Lemna pausicostata), and compared with mammalian toxicity estimated in vitro with four mammalian cell lines. On duckweed, both phenanthrene derivatives caused electrolyte leakage, chlorophyll loss and photobleaching. Ultrastructural examination of duckweed frond and root tissues treated with gymnopusin (100 μM) revealed membrane damage to the tonoplast after 12 h of exposure. Effects on membrane integrity followed a time course similar to that of electrolyte leakage. Both phenanthrene derivatives exhibited moderate cytotoxicity to all mammalian cells tested, which precludes their use as a bioherbicide.
20 citations