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Application of HPLC-NMR coupling using C30 phase in the separation and identification of flavonoids of taxonomic relevance
(2000-12-01)
The on-line separation and identification of two important taxonomic markers for plant species of the Paepalanthus genus, the flavonoids 6-methoxykaempferol-3-O-β-D-glucopyranoside and 6-methoxykaempferol-3-O-β-D-6″(p-co ...
Triterpenes and saponins from Rudgea viburnioides
(1998-07-01)
A novel triterpene; viburgenin (1), has been isolated from an extract of the ripe fruit rinds of Rudgea viburnioides, together with the known saponins, arjunglucoside I and trachelosperosides B-1 and E-l, and the triterpenes ...
Encapsulation of titanium (IV) silsesquioxane into the NH4USY zeolite: Preparation, characterization and application
(Elsevier B.V., 2007-10-02)
This work describes the encapsulation of titanium (IV) silsesquioxane into the supercavities of NH4USY ultra stabilized zeolite, after chemical treatment. The modified zeolite was characterized by Fourier transform infrared ...
Ferrocene adsorbed into the porous octakis(hydridodimethylsiloxy) silsesquioxane after thermolysis in tetrahydrofuran media: An applied surface for ascorbic acid determination
(Pergamon-Elsevier B.V. Ltd, 2012-04-01)
Octakis(hydridodimethylsiloxi)silsesquioxane (Q(8)M(8)(H)) was synthesized and Ferrocene was adsorbed in a polymeric net through electrostatic interactions, with anion forming after the cleavage of any siloxy groups (ESFc). ...
Experimental NMR and MS study of benzoylguanidines. Investigation of E/Z isomerism
(2013-04-01)
Molecules containing the guanidinic nuclei possess several pharmacological applications, and knowing the preferred isomers of a potential drug is important to understand the way it operates pharmacologically. Benzoylguanidines ...
Hyperfine interaction in Zn-Al layered double hydroxides intercalated with conducting polymers
(Pergamon-Elsevier B.V. Ltd, 2008-05-01)
Organic-inorganic hybrid materials based on the assembly between inorganic 2D host structure and polymer have received considerable attention in the last few years. This emerging class of materials presents several ...
A new tropane alkaloid and other constituents of Erythroxylum rimosum (Erythroxylaceae)
(2013-05-01)
A new tropane alkaloid, named the 7β-acetoxy-3β,6β- dibenzoyloxytropane (1), was isolated from a methanol extract of Erythroxylum rimosum O.E. Schulz leaves. Other known compounds were detected, including quercetin, ...
Photodegradation of sparfloxacin and isolation of its degradation products by preparative HPLC
(2005-12-01)
Sparfloxacin, a third generation fluoroquinolone derivative, is a potent antibacterial agent active against a wide range of Gram-positive and Gram-negative organisms including Streptococcus pneuinoniae, Staphylococcus ...
A new ent-kaurane diterpene from stems of Alibertia macrophylla K. Schum. (Rubiaceae)
(2007-10-11)
Phytochemical investigations of the stems of a specimen of Alibertia macrophylla led to the isolation and characterization of the new diterpene ent-kaurane-2β,3α,16α-triol (1), along with triterpenes 2-8, iridoids 9-12, ...
Chemistry and bioactivity of Raulinoa echinata Cowan, an endemic Brazilian rutaceae species
(2001-04-17)
The hexane extract of the stems of Raulinoa echinata afforded the sesquiterpenes germacrene D (6), 1β,6α-dihydroxy-4-(15)-eudesmene (4) and oplopanone (5); the triterpenes squalene, isomultiflorenol (7), isobauerenol (8) ...