Search results for "Terpene"
showing 10 items of 816 documents
Terracinolides from Euphorbia terracina
1997
Abstract The aerial parts of Euphorbia terracina yielded five new bishomoditerpene lactones, named terracinolides C-G, which display the novel C 22 17-ethyljatrophane framework.
Sesquiterpene lactones, waxes and volatile compounds from Artemisia herba-alba subspecies Valentina
1979
Abstract The structures of two sesquiterpene lactones isolated from Artemisia herba-alba subsp. valentina have been determined by spectroscopic methods. One of these was dihydroreynosin, the other was a new compound assigned the name torrentin. The chemical compositions of a wax and a hydrocarbon fraction from the essential oil have also been investigated.
Monoterpenes in grape juice and wines.
2000
The importance of monoterpenes on varietal flavour of wines has been reviewed. These compounds were mainly found linked to sugar moieties in the grape juice and wines, showing no olfactive characteristics. In this way, mechanisms to liberate terpenes were studied, making a comparative study between acidic and enzymic hydrolysis of terpene glycosides. Finally, analytical techniques developed to study these compounds, in both free or glycosidically forms, and also to fractionate glycosidic precursors, have been discussed.
Sesquiterpene lactones from Artemisia hispanica
1989
Abstract Extraction of aerial parts of Artemisia hispanica and chromatographic separation yielded the eight known sesquiterpene lactones costunolide, artemorin, anhydroverlotorin, tamaulipin A, reynosin, santamarin, matricarin and deacetylmatricarin, the flavone cirsimaritin, zingerone, 1-hydroxy-α-bisabololoxide A acetate and the new germacranolide 2α-hydroxyartemorin.
Biological Activities of Natural Sesquiterpene Lactones and the Effect of Synthetic Sesquiterpene Derivatives on Insect Juvenile Hormone Biosynthesis
1998
Three natural sesquiterpene lactones have been assayed for their biological activity on locust (Locusta migratoria) nymphs. Since results obtained in vivo pointed to disruptions on juvenile hormone (JH)-regulated physiology, we tested the sesquiterpene lactones and a family of synthetic sesquiterpene derivatives for their ability to disturb the rate of JH biosynthesis by locust corpora allata (CA) in vitro. All the active compounds in vitro share a basic sesquiterpene double-ring structure as well as substituents with different chemical complexities. Compounds that shared an eudesmane base with different oxidation states on C3 and C12 carbon atoms were tested as JH biosynthesis inhibitors. …
Sesquiterpene lactones from Anthemis plutonia.
1998
Abstract Aerial parts of Anthemis plutonia furnished three guaianolides, one of them new.
Ursane-Type Triterpene Saponins fromZygophyllum geslini
2007
Four new ursane-based triterpene glycosides, compounds 1–4, as well as the known glycosides zygophylosides E, G, and H, and 3-O-(β-D-quinovopyranosyl)quinovic acid 28-(O-β-D-glucopyranosyl) ester, were isolated from the BuOH-soluble fraction of the MeOH/H2O 7 : 3 extracts of Zygophyllum geslini (roots or aerial parts). Their structures were established mainly by 1D- and 2D-NMR techniques, in combination with HR-MS analysis and acid hydrolysis.
ChemInform Abstract: Dysidotronic Acid, a New and Selective Human Phospholipase A2 Inhibitor from the Sponge Dysidea sp.
2010
Abstract A new bioactive sesquiterpenoid, named dysidotronic acid 1, with a rearranged drimane skeleton has been isolated from the sponge Dysidea sp. from Vanuatu islands, along with bolinaquinone 2. The chemical structure of 1 was determined on the basis of spectroscopic data. Dysidotronic acid significantly inhibited human synovial phospholipase A2 (PLA2) at 10 μM, with an IC50 value of 2.6 μM and a higher selectivity and potency towards this enzyme than the reference inhibitor manoalide.
Dammarane triterpenes of Salvia hierosolymitana
1990
Abstract Salvilymitone and salvilymitol, two new triterpenoids isolated from Salvia hierosolymitana , have been shown to be 7β,25-dihydroxy-(20 S ,24 R )-epoxydammaran-3-one and (20 S ,24 R )-epoxydammaran-3β,7α,25-triol, respectively. The absolute stereochemistry of these triterpenoids has been established by an X-ray diffraction analysis of a 25,26,27-trinor derivative obtained by degradation of both compounds. In addition, four previously known triterpenoids were isolated from the same source.
Ingenane and lathyrane diterpenes from the latex of Euphorbia canariensis
1997
The latex of Euphorbia canariensis yielded, in addition to five known ingenol esters, the ingenane derivatives ingenol 3-angelate 5,20-diacetate and 5-deoxyingenol 3-angelate 20-acetate, and the lathyrane derivatives 2,3-diepiingol 7,12-diacetate 8-benzoate, 2,3-diepiingol 7,12-diacetate 8-isobutyrate and 2-epiingol 3,7,12-triacetate 8-benzoate. The structures were established with the aid of spectroscopic methods, mainly NMR, and molecular mechanics calculations. They were also supported by the results of some chemical transformations.