Search results for "Pharmacognosy"
showing 10 items of 127 documents
Three New Oleanane Saponins from Zanha africana
1997
Three new saponins, zanhasaponins, A, B, and C, were isolated from the MeOH extract of the root bark of Zanha africana and were, respectively, identified by spectroscopic methods as 3-O-beta-D-glucuronopyranosyl-2 beta,16 alpha-dihydroxyolean-12-ene-23,28- dioic acid 28-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-rhamnopyranoside (1); 3-O-beta-D-glucuronopyranosyl-2 beta,16 alpha-dihydroxyolean-12-ene- 23,28-dioic acid 28-O-beta-D-xylopyranosyl(1-->2)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L- rhamnopyranoside (2); and 3-O-beta-D-glucuronopyranosyl-2 beta,16 alpha-dihydroxyolean-12-ene- 23,28-dioic acid 28-O-beta-D-xylopyranosyl(1-->3)-beta-D-xylopyranosyl (1-->2)-alpha-L-rhamnopyranosyl(1-->2)-a…
Jenisseensosides C and D, biologically active acylated triterpene saponins from Silene jenisseensis
1997
Abstract We previously reported the isolation and structure elucidation of a new trans - p -methoxycinnamoyl triterpene-saponin along with its cis - p -methoxycinnamoyl isomer as an inseparable mixture from the roots of Silene jenisseensis . In a continuing study on this plant, two additional new acylated triterpene-saponins were obtained as an inseparable mixture. Their structures have been established by chemical means and spectroscopic methods including 1D and 2D homonuclear and heteronuclear correlation NMR spectroscopy as 3- O -[β- d -galactopyranosyl-(1 → 2)-β- d -glucuronopyranosyl]-28- O -[{α- l -rhamnopyranosyl-(1 → 2)}- {4- O - trans - p -methoxycinnamoyl}-β- d -fucopyranosyl] qui…
Chromone and phenanthrene alkaloids from Dennettia tripetala.
2002
Dennettine, a new 2,6-dimethoxychromone and three known phenanthrene alkaloids (uvariopsine, stephenanthrine and argentinine) in addition to the phenolic and known compound vanillin were isolated from the roots of Dennettia tripetala. Their structures were determined by physical and spectroscopical one dimensional (1D) and 2D-NMR analysis, including heteronuclear multiple bond correlation and nuclear Overhauser enhancement spectroscopy.
Two New Glycosides from Astragalus caprinus
2001
A new glycoside of flavonol (1) and a new glycoside of a cycloartane-type triterpene (2) were isolated from the leaves and the roots of Astragalus caprinus, respectively. Their structures were elucidated in turn by spectroscopic data interpretation as 3-O-[[beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)][beta-D-apiofuranosyl(1-->2)]]-beta-D-galactopyranosyl kaempferol (1) and 3-O-(beta-D-xylopyranosyl)-24-O-(beta-D-glucopyranosyl)-20,25-epoxycycloartane-3beta,6alpha,16beta,24alpha-tetrol (2).
Antispasmodic Effects and Structure−Activity Relationships of Labdane Diterpenoids from Marrubium globosum ssp. libanoticum
2009
Marrubium globosum ssp. libanoticum is a medicinal plant used in Lebanon to reduce pain and smooth muscle spasms. A chloroform extract obtained from M. globosum aerial parts reduced acetylcholine-induced contractions in the isolated mouse ileum. The purification of this extract identified, among 12 isolated labdane diterpenoids, four new compounds, named 13-epicyllenin A (4), 13,15-diepicyllenin A (5), marrulibacetal (9), and marrulactone (11). Their structures were determined by spectroscopic methods. Compound 9, which exerted antispasmodic activity, is likely the active ingredient of the extract. Preliminary structure-activity relationships for this class of compounds are suggested.
Phytochemical and pharmacological studies on the acetonic extract of Marrubium globosum ssp. libanoticum
2006
A new natural labdane diterpene, marrulibanoside, was isolated from the acetonic extract of aerial parts of M. globosum Montbr. et Auch. ex Benth. ssp. libanoticum Boiss. (Lamiaceae). Its structure was determined by spectroscopic methods such as 1D and 2D NMR and mass spectrometry. Pharmacological studies have shown that the extract of M. globosum exerts anti-inflammatory effects in the rat paw oedema induced by carrageenin resulting in reduced paw swelling. This activity, which seems due to marrulibanoside, is a consequence of iNOS and COX-2 activities inhibition.
A hypotensive procyanidin-glycoside from Rhamnus lycioides ssp. lycioides.
1990
A lyophilized hot water extract of the aerial parts of Rhamnus lycioides L. (Rhamnaceae) produced a lowering of systemic arterial blood pressure in normotensive anaesthetized Wistar rats. An activity-guided fractionation of the methanolic extract led to the isolation of a tetrameric procyanidin-glycoside which produced a clear dose-dependent hypotensive response (1.5-6 mg/kg i.v.). This principle was characterized using acid hydrolysis, thiolytic degradation and spectroscopic methods. It consisted of four flavanol units with a 2,3-cis configuration and with a O-beta-d-glucosylpyranoside function on the epicatechin terminal unit. The interflavan linkage was (4-8).
Anti-inflammatory compounds from Sideritis javalambrensis n-hexane extract.
1989
The anti-inflammatory activities of the n-hexane extract of Sideritis javalambrensis and several purified fractions were investigated using the carrageenan mouse paw edema test. Progressive fractionation led to the isolation of the active principles ent-16-hydroxy-13-epimanoyl oxide [1] and esters of tyrosol with palmitic, stearic, behenic, and lignoceric acids.
Antinociceptive and anti-inflammatory activities of Acacia pennata wild (Mimosaceae)
2005
The butanolic fraction of dried leaves of Acacia pennata (Mimosaceae) was tested for analgesic and anti-inflammatory activities in animal models. It showed significant protective effects against chemical stimuli (acetic acid and formalin) in the mouse. It also produced a significant increase of the threshold of sensitivity to pressure-induced pain in the rats. The extract revealed an inhibitory effect in carrageenin-induced rat paw oedema in the late phase. The results suggested that a peripheral mechanism is involved in the analgesic, associated to anti-inflammatory effect (NSAIDs-like). Among the class of compounds characterized in this fraction, flavonoids may be mainly responsible for t…
Pharmacological Screening of DifferentJuniperus oxycedrusL. Extracts
1998
Methanol and dichloromethanol extracts of leaves and stems of Juniperus oxycedrus have been tested for their toxicity, analgesic, antiinflammatory and central effects. Both extracts showed low acute toxicity and decreased spontaneous motility. The methanol extract exhibited an analgesic effect in models of chemical, mechanical and thermal stimulation whereas dichloromethanol extract showed only a significant effect in models of pain induced by chemical stimulation. Both extracts showed a significant antiinflammatory activity and inhibition of the rat paw oedema induced by carrageenin.