Search results for "Terpene"
showing 10 items of 816 documents
New sesquiterpene lactones and acetylenes from chrysanthemum lavandulifolium
1990
Abstract The aerial parts of Chrysanthemum lavandulifolium Mak. (Asteraceae) yielded three new acetylenes of the spiroacetal type 1-3, as well as two new germacranolides 4-5 and several known lactones.
New Triterpenoidal Saponins fromGypsophila repens
2007
Six new triterpene glycosides, repensosides A–F (1–6, resp.), were isolated from the roots of Gypsophila repens L. Their structures, established by extensive 1D- and 2D-NMR spectroscopic experiments as well as MS analyses, were found to be based on gypsogenic acid (or gypsogenin) as aglycone, with three to nine branched or unbranched sugar moieties.
Synthetic studies on neoclerodane diterpenes from Salvia splendens: oxidative modifications of ring A.
2011
Salvinorin A (1), a neoclerodane diterpene from the hallucinogenic mint Salvia divinorum, is the only known naturally occurring non-nitrogenous and specific κ-opioid agonist. Some oxidative modifications of the A ring in the congeners of 1 isolated from Salvia splendens salviarin, splenolide B, splendidin and in the non-natural 8-epi-salviarin gave new derivatives, some of which were tested as agonists at opioid receptors. However, none of these compounds were active. The presence of the C-18, C-19 lactone could be at the origin of the observed lack of binding affinity.
Triterpene Saponins from Four Species of the Polygalaceae Family
2005
Twelve triterpene saponins were isolated by successive MPLC over silica gel from four species of Polygalaceae: From Polygala ruwenzoriensis, five new saponins 1–5 of which 1–4 as two pairs of (E)/(Z)-isomers, together with the four known compounds tenuifoline, (E)- and (Z)-senegasaponin b, (E)- and (Z)-senegin II, and polygalasaponin XXVIII, from the genus Carpolobia, one new saponin 6 from C. alba and the known arilloside (11) from C. lutea, and another new triterpene glycoside 7 from Polygala arenaria. Their structures were established mainly by 600-MHz 2D-NMR techniques (1H,1H-COSY, TOCSY, NOESY, HSQC, HMBC) as 3-O-(β-D-glucopyranosyl)presenegenin 28-{O-α-L-arabinopyranosyl-(1 4)-O-β-D-…
New Acylated Triterpene Saponins fromPolygala arenaria
2003
Eight new acylated triterpene saponins 1–8 were isolated from the roots of Polygala arenaria as four inseparable (E)/(Z) mixtures of the 4-methoxycinnamoyl and 3,4-dimethoxycinnamoyl derivatives by repeated MPLC over silica gel. Their structures were established mainly by 600-MHz 2D-NMR techniques (1H,1H-COSY, TOCSY, NOESY, HSQC, HMBC) as 3-O-(β-D-glucopyranosyl)presenegenin 28-(O-β-D-galactopyranosyl-(14)-O-[β-D-glucopyranosyl-(13)]-O-β-D-xylopyranosyl-(14)-O-α-L-rhamnopyranosyl-(12)-{4-O-[(E)-4-methoxycinnamoyl]}-β-D-fucopyranosyl) ester and its (Z)-isomer (1/2), 3-O-(β-D-glucopyranosyl)presenegenin 28-(O-β-D-galactopyranosyl-(14)-O-[β-D-glucopyranosyl-(13)]-O-β-D-xylopyranosyl-(14)-O-α-L…
Oxygenated germacranes from Santolina chamaecyparissus
1993
The polar fraction of an extract of Santolina chamaecyparissus ssp. squarrosa yielded six new germacrane derivatives and a novel seco-germacrane lactone. The structures have been derived from spectral data, X-ray diffraction and chemical correlations.
Metabolic cross-talk between pathways of terpenoid backbone biosynthesis in spike lavender
2015
Abstract The metabolic cross-talk between the mevalonate (MVA) and the methylerythritol phosphate (MEP) pathways in developing spike lavender ( Lavandula latifolia Med) was analyzed using specific inhibitors and on the basis of 13 C-labeling experiments. The presence of mevinolin (MEV), an inhibitor of the MVA pathway, at concentrations higher than 0.5 μM significantly reduced plant development, but not the synthesis of chlorophylls and carotenoids. On the other hand, fosmidomycin (FSM), an inhibitor of the MEP pathway, at concentrations higher than 20 μM blocked the synthesis of chlorophyll, carotenoids and essential oils, and significantly reduced stem development. Notably, 1.2 mM MVA cou…
Saponins as immunoadjuvants and immunostimulants
1999
Saponins are either triterpene or steroid glycosides widely distributed in the plant and animal kingdom and include a large number of biologically active compounds. Most of them have surface-active and cholesterol-binding properties.
The Synthesis of Bioactive Sesquiterpenes from Santonin
2000
Abstract This article reviews the literature published in the last decade dealing with the transformation of α-santonin into bioactive or potentially bioactive sesquiterpenes. A number of syntheses starting from 8α-hydroxysantonin (artemisin) have also been included. Special emphasis has been placed on synthesized products that show biological activity. Major advances in this field include the application of new reagents and methodologies for the structural modification of the santonin skeleton and functionality, and its transformation into other sesquiterpenes, especially sesquiterpene lactones. The review has been organised into five parts: 1. Introduction: An overview of the structure an…