Search results for "Complementary"
showing 10 items of 1156 documents
Triterpene Saponins from the Fruits of Phytolacca rugosa (Phytolaccaceae)
2010
Four known serjanic acid glycosides were isolated from the fruits of Phytolacca rugosa and characterized mainly by 2D NMR spectroscopy and mass spectrometry. This aglycon has a chemotaxonomic significance for the genus Phytolacca.
Antiproliferative oleanane saponins from Polyscias guilfoylei
2008
Three new oleanane saponins (1–3), together with four known ones (4–7), were isolated from the aerial parts of Polyscias guilfoylei. Their structures were elucidated by 1D and 2D NMR experiments, including 1D TOCSY, DQF-COSY, ROESY, HSQC, and HMBC spectroscopy, as well as ESIMS analysis. The antiproliferative activity of all compounds was evaluated using three murine and human cancer cell lines; J774.A1, HEK-293, and WEHI-164. All the compounds were inactive except for 3β- O-[β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl]-echinocystic acid 28-[ O-β-D-glucopyranosyl-(1→6) O-β-D-glucopyranosyl] ester (3), which was active against all the cell lines.
New Diosgenin Glycosides from Costus afer
1997
Two new steroidal saponins, aferosides B (1) and C (2), together with the known saponins, dioscin (3) and paryphyllin C (4), were isolated from the roots of Costus afer. The known flavonoid glycoside, kaempferol 3-O-α-l-rhamnopyranoside (5), was obtained from the aerial parts. The structures of the new compounds were elucidated principally by 2D NMR spectral methods. A structural revision of the sugar sequence was made for the previously reported saponin aferoside A (6) on the basis of detailed spectroscopic analysis. Saponins 1−4 and 6 did not show any ability to potentiate in vitro cisplatin cytotoxicity in a human colon cancer cell line.
Neoclerodane Diterpenoids from Scutellaria polyodon
1997
Nine new neoclerodane diterpenoids, scupolins A−I, have been isolated from an Me2CO extract of the aerial parts of Scutellaria polyodon (3−11), together with the known neoclerodanes jodrellin B (1) and scutecolumnin A (2). Structures 3−11 were established by spectroscopic means and by comparison with closely related compounds.
Two New Oleanane-type Saponins from Hydrocotyle multifida
2018
A phytochemical study of a Venezuelan species Hydrocotyle multifida led to the isolation of five oleanane-type glycosides: two previously undescribed and three known ones. Their structures were established by 2D NMR spectroscopic techniques and mass spectrometry as 3- O-β-D-galactopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucuronopyranosyloleanolic acid and 3- O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyrano-syloleanolic acid. These results represent a significative contribution to the chemotaxonomy of the Hydrocotyle genus.
8-NH2-Boldine, an Antagonist of α1Aand α1BAdrenoceptors without Affinity for the α1DSubtype: Structural Requirements for Aporphines at α1-Adrenocepto…
2005
Structure-activity analysis of 21 aporphine derivatives was performed by examining their affinities for cloned human alpha (1A), alpha (1B) and alpha (1D) adrenoceptors (AR) using membranes prepared from rat-1 fibroblasts stably expressing each alpha (1)-AR subtype. All the compounds tested competed for [ (125)I]-HEAT binding with steep and monophasic curves. The most interesting compound was 8-NH (2)-boldine, which retains the selective affinity for alpha(1A)-AR (pKi = 6.37 +/- 0.21) vs. alpha(1B)-AR (pKi = 5.53 +/- 0.11) exhibited by 1,2,9,10-tetraoxygenated aporphines, but shows low affinity for alpha(1D)-AR (pKi < 2.5). Binding studies on native adrenoceptors present in rat cerebral cor…
Neoclerodane Diterpenoids from Teucrium massiliense
1998
A reinvestigation of the diterpene metabolites of Teucrium massiliense L. allowed the isolation of four new neoclerodane derivatives, teumassilenins A-D, together with all the diterpenoids previously reported as constituents of this plant. The structures of the new compounds (1-4) were established by chemical and spectroscopic means. A plausible biogenetic relationship between several of these substances is briefly discussed, and some unpublished physical and spectroscopic data of the previously known diterpenoid teumassin (5) are now reported.
X-ray Crystal Structure of Woodinine and Conformational Analysis by Semiempirical and 1H-NMR Methods
1997
The mol. structure of (-)-woodinine (I), a carboline-based alkaloid with antibacterial and antimycobacterial activities, was investigated by X-ray crystallog., NMR, and semiempirical quantum chem. methods. The X-ray crystal structure of I showed the indole ring in the expected planar conformation, the pyrrolidine ring in an envelope conformation, and a weak intramol. hydrogen bond between the pyrrolidine nitrogen and the proton of the indole nitrogen. NMR expts. indicated that this hydrogen bond is not present in soln. and that further differences exist between the crystal and the soln. structures of I. By semiempirical quantum chem. methods, different local energy min. conformations of I, …
Metabolites from the Aerial Parts of the Sicilian Population of Artemisia alba
2013
Phytochemical investigation of the CH2Cl2 extract of the aerial parts of Artemisia alba Turra afforded one new irregular sesquiterpenoid, artemiric acid, and five known metabolites: hydroxydavanone, the coumarins isofraxidin and scopoletin, (6 S*,7 S*,10 R*)–6,10-dimethyl-7,10-epoxyocta-11-enoic acid and artalbic acid. From the MeOH extract three flavonoids were identified: chrysoeriol, quercetin and isorhamnetin. The possible biogenetic pathways of artemiric and artalbic acids are discussed.
Chemical composition of the essential oils of Centaurea sicana and C. giardinae growing wild in Sicily
2008
The essential oils of Centaurea sicana (S) and C. giardinae (G) were studied by GC and GC-MS. Thirty constituents for S, representing 81.5% of the total oil, and 24 compounds for G (94.2% of the total) were identified. The oils were rich in sesquiterpenoids (47.9% for S and 54.7% for G) and hydrocarbons (25.9% for S and 31.7% for G). Germacrene D (13.3%), ( E)-β-farnesene (8.3%), nonacosane (7.3%), heptacosane (6.5%) and phytol (6%) were recognized as the main constituents for S, while caryophyllene oxide (17.7%), nonacosane (14.5%), germacrene D (11.5%), caryophyllene (11.2%) and heptacosane (10.3%) were the main compounds for G.