Search results for "sesquiterpenes"
showing 10 items of 110 documents
QSAR of Natural Sesquiterpene Lactones as Inhibitors of Myb-dependent Gene Expression
2017
Background Protein c-Myb is a therapeutic target. Some sesquiterpene lactones suppress Myb-dependent gene expression, which results in their potential anti-cancer activity. Material & methods Database ChEMBL is a representative of lactones for physicochemical and physiochemical properties. Data presented for 31 natural lactones are discussed in terms of quantitative structureactivity relationships with the objective to predict inhibitors of Myb-induced gene expression. Several constitutional descriptors are related to structure-activity. α-Methylene-γ-lactone groups enhance while OH functions worsen potency. The latter feature is in agreement with the fact that the more lipophilic the lacto…
Synthesis and application of β-substituted Pauson-Khand adducts: trifluoromethyl as a removable steering group.
2013
The reaction between alkynes (I) and norbornadiene (II) affords the β-substituted Pauson—Khand adducts (III) as single regioisomers and the trifluoromethyl steering group can be easily removed in the presence of DBU and water.
A novel caryophyllene type sesquiterpene lactone from Asparagus falcatus (Linn.); Structure elucidation and anti-angiogenic activity on HUVECs
2011
Abstract In this study the novel caryophyllene type sesquiterpene lactone (aspfalcolide) has been isolated from the leaves of Asparagus falcatus (Linn.) and characterized by IR, 1D NMR, 2D NMR, EI–MS, HR–ESI–MS and X-ray single crystal diffraction analysis. The aspfalcolide crystallizes in the orthorhombic space group P212121 with a = 6.37360(10), b = 7.6890(2), c = 27.3281(6) A, α = β = γ = 90° and Z = 4. One intermolecular O–H⋯O hydrogen bond enforces these natural molecules to form infinite chains through the crystal. Aspfalcolide was screened for its anti-angiogenic activity in human umbilical vein endothelial cells (HUVECs) and the result showed the remarkable inhibitory effect of aspf…
Dysidotronic acid, a new sesquiterpenoid, inhibits cytokine production and the expression of nitric oxide synthase.
2001
In a previous study, we reported a new bioactive sesquiterpenoid, named dysidotronic acid, to be a potent, selective human synovial phospholipase A(2) inhibitor. Dysidotronic acid is a novel, non-complex manoalide analogue lacking the pyranofuranone ring. We now investigate the effect of this compound on cytokine, nitric oxide and prostanoid generation on the mouse macrophage cell line RAW 264.7, where it showed a dose-dependent inhibition with inhibitory concentration 50% values in the micromolar range. This effect was also confirmed in the mouse air pouch injected with zymosan. Dysidotronic acid inhibited the production of tumor necrosis factor alpha and interleukin-1 beta as well as the …
Cytotoxic activity of some natural and synthetic guaianolides
2005
Several natural guaianolides and synthetic derivatives of repin (1) were tested and found to be active against tumor cell replication. Repin (1) and both mono- and di-halohydrin analogues (2, 7-9, 11, 12) showed significant antitumor potency. A more effective compound (17) was obtained by esterificating repin with the paclitaxel side chain.
Volatile constituents of Stachys palaestina L. (Palestine woundwort) growing in Lebanon
2014
The hydrodistillation of the aerial parts of Stachys palaestina L. collected in Lebanon in the Kadisha Valley, yielded 0.1% (w/w) of essential oil. GC and GC-MS analyses enabled the identification of 87 compounds representing 90.8% of the total oil. Hexadecanoic acid (10%), hexahydrofarnesyl acetone (6.9%), eugenol (4.3%) and (E)-caryophyllene (4.3%) were the main components. On the whole, the oil was constituted mainly of sesquiterpenes (37.7%), among which sesquiterpene hydrocarbons (20.7%) slightly prevailed over oxygenated sesquiterpenes (17.0%). This is the first report on the chemical composition of S. palaestina essential oil.
Cytotoxic and protein kinase inhibiting nakijiquinones and nakijiquinols from the sponge Dactylospongia metachromia.
2014
Chemical investigation of the sponge Dactylospongia metachromia afforded five new sesquiterpene aminoquinones (1-5), two new sesquiterpene benzoxazoles (6 and 7), the known analogue 18-hydroxy-5-epi-hyrtiophenol (8), and a known glycerolipid. The structures of all compounds were unambiguously elucidated by one- and two-dimensional NMR and by MS analyses, as well as by comparison with the literature. Compounds 1-5 showed potent cytotoxicity against the mouse lymphoma cell line L5178Y with IC50 values ranging from 1.1 to 3.7 μM. When tested in vitro for their inhibitory potential against 16 different protein kinases, compounds 5, 6, and 8 exhibited the strongest inhibitory activity against AL…
Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth) Don ssp. italicum
2011
The chemical composition of the essential oil of Helichrysum italicum (Roth) Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected.
Sterelactones: New Isolactarane Type Sesquiterpenoids with Antifungal Activity from Stereum sp. IBWF 01060
2008
Four members of a new family of tetracyclic sesquiterenoids possessing the isolactarane skeleton have been isolated from mycelial cultures of Stereum sp. IBWF 01060. Their structure elucidation and their antifungal activity against several plant pathogens as well as other microorganisms are reported.
A Bioinspired Approach to Tri-nor-guaianes. Synthesis of (−)-Clavukerin A
2006
A bioinspired approach to tri-nor-guaianes by degradation of the C-7 side chain of related guaia-11-enes is described. In this approach (-)-clavukerin A (1) is obtained by selective ozonolysis-Criegge rearrangement of (+)-1alphaH,7alphaH,10alphaH-guaia-4,11-dien-3-one (4) to afford 7beta-hydroxy and 7beta-acetoxy tri-nor-guaiane derivatives 6 and 7, respectively, which after elimination and deoxygenation give the title compound. The starting guaiadienone is readily obtained from commercially available santonin or (+)-dihydrocarvone.