14 resultados
The chloroform solvate of uncarine C (pteropodine), (1'S,3R,4'aS,5'aS,10'aS)-1,2,5',5'a,7',8',10',10'a-octahydro-1'-methyl-2-oxospiro[3H-indole-3,6'(4'aH)-[1H]pyrano[3,4-f]indolizine]-4'-carboxylic acid methyl ester, C(21)H(24)N(2)O(4).CHCl(3), has an absolute configuration with the spiro C atom in
OBJECTIVE
To study the alkaloidial constituents of the leaves of uncaria hirsuta.
METHODS
Some chromatographic methods were applied to isolate pure compounds and their structures were elucidated by spectroscopic methods.
RESULTS
Eleven compounds were isolated and identified as
Four new alkaloids, comprising three 3-oxo-3,7-seco-oxindole alkaloids (hirsutanine D-F, 1-3) and one oxindole alkaloid N-oxide (uncarine B N-oxide, 4), together with four known heteroyohimbine-type oxindole alkaloids, were isolated from the stems of Uncaria hirsuta Havil. Structures of 1-4 were
Bioassay-guided fractionation of the EtOH extract of the bark of Uncaria guianensis (Aubl.) Gmel (Rubiaceae) using a yeast-based assay for DNA-damaging agents has furnished the two weakly but selectively active indole alkaloids uncarine C (1) and uncarine E (2) as the major bioactive constituents in
pH-Zone refining counter-current chromatography was successfully applied to the preparative isolation and purification of six alkaloids from the ethanol extracts of Uncaria macrophylla Wall. Because of the low content of alkaloids (about 0.2%, w/w) in U. macrophylla Wall, the target compounds were
The effects of Uncaria tomentosa total alkaloid and its oxindole alkaloid components, uncarine E, uncarine C, mitraphylline, rhynchophylline and isorhynchophylline, on the impairment of retention performance caused by amnesic drugs were investigated using a step-down-type passive avoidance test in
The alkaloids of Uncaria tomentosa micropropagated plantlets and root cultures were isolated and identified by NMR and mass spectrometry. Plantlets yielded pteropodine (1), isopteropodine (2), mitraphylline (3), isomitraphylline (4), uncarine F (5), speciophylline (6), rhynchophylline (7) and
The alkaloid and procyanidin composition of Uncaria sp. from eastern Peru, used in folk medicine was studied. Five alkaloids have been separated and identified as pteropodine, speciophylline, isopteropodine, uncarine F and isomytraphylline, all belonging to the oxindole group characteristic of the
Oxindole alkaloids, isolated from the bark of Uncaria tomentosa [Willd. ex Schult.] Rubiaceae, are considered to be responsible for the biological activity of this herb. Five pentacyclic and two tetracyclic alkaloids were studied by solid-state NMR and theoretical GIAO DFT methods. The (13)C and
The purpose of this study was to examine the effect of orally administered Uncaria tomentosa aqueous extracts (UTE) (Willd. ex Roem. & Schult.) DC. (Rubiaceae) during 7, 15, 30 and 90 days of treatment on the expression of anxiety, as expressed in the elevated plus maze test in male Albino Swiss
Natural products are still an untapped source of promising lead compounds for the generation of antineoplastic drugs. Here, we investigated for the first time the antiproliferative and apoptotic effects of highly purified oxindole alkaloids, namely isopteropodine (A1), pteropodine (A2),
The C-8-(S) isomer of deoxyloganic acid (7-deoxyloganic acid), together with beta-sitosteryl glucoside, five known stereoisomeric pentacyclic oxindole alkaloids and the tetracyclic oxindole isorhyncophylline, were isolated from the inner bark of Uncaria tomentosa. Structures of the isolated