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3.
Izv Akad Nauk Ser Biol ; (4): 493-6, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10520291

RESUMO

We studied membranotropic effect of dammarane-type triterpenes (isolated from birch leaves) with a variable side chain structure, as well as the number and configuration of OH groups as a function of temperature and pH. Polyols with an acyclic side chain and four OH groups proved to have a higher hemolytic activity as compared to polyols with three or five hydroxyl groups. The triterpenes, with tetrahydrofurane cycle as the side chain, exert a hemolytic effect at a more acidic pH (5.0) and higher temperature (45 degrees C), as compared to the polyols with acyclic side chain. Irrespective of the side chain structure, the compounds with a 24(S) configuration lysed the erythrocytes at lower rate, as compared to the compounds with a 24(R) configuration.


Assuntos
Hemólise/efeitos dos fármacos , Esteroides/farmacologia , Triterpenos/farmacologia , Animais , Eritrócitos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Camundongos , Extratos Vegetais/farmacologia , Folhas de Planta , Relação Estrutura-Atividade , Temperatura , Árvores , Damaranos
4.
Planta Med ; 65(1): 30-4, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10083841

RESUMO

The cytotoxicity of natural glycosides from Ginseng, semisynthetic analogues and related triterpenes of the dammarane series, isolated from the leaves of the Far-East species of the genus Betula was studied in order to elucidate structure-activity relationships. Some of the compounds studied were active against the human lung carcinoma GLC4 and adenocarcinoma COLO 320 cell lines. The natural glycosides displayed the lowest cytotoxicity. The triterpenes of the dammarane series used as starting aglycones for semisynthetic derivatives were moderately cytotoxic. The dammarane triterpenes possessing keto groups and their semisynthetic glucosides were the most active compounds tested. Cytotoxic effects of the dammarane glucosides were inversely proportional both to the number of sugars attached to the aglycones and to the number of hydroxy groups of the aglycones. The type of side chain and the configuration of the hydroxy group at C-3 in aglycones did not have a significant influence on the cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Glicosídeos/farmacologia , Panax/química , Plantas Medicinais , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Humanos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Carbohydr Res ; 304(2): 179-82, 1997 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-9527441

RESUMO

Glycosylation of 12beta-acetoxy-dammar-24-en-3beta,20(S)-diol (4), with hepta-O-acetyl-alpha-sophorosyl bromide (5) under catalysis by Ag2CO3 or Ag2O afforded a chromatographically unseparated mixture of the alpha- and beta-linked octaacetates 6 and 7 in an approximately 2.5:1 ratio. After deprotection and chromatographic purification, the free alpha- (8) and beta-glycosides (9) were obtained. Sophoroside 9 was identical in all respects with ginsenoside Rg3, the minor component of Ginseng Radix rubra. All compounds were fully characterized by 1H and 13C NMR spectroscopy.


Assuntos
Ginsenosídeos , Panax/química , Plantas Medicinais , Saponinas/síntese química , Acetilação , Glicosilação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Saponinas/química , Saponinas/isolamento & purificação
7.
Antibiot Khimioter ; 39(9-10): 19-25, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7695444

RESUMO

Immunomodulating activity of triterpene glycosides of the holostan series (holoturins A and B, holoturin A2 and holotoxin A1) and triterpene glycosides of the dammaran series (3-O-monoglycoside,12-O-monoglycoside and 20-O-monoglycoside of protopanaxadiol and 3-O-monoglycoside of betulafolientriol) was studied in vitro. In low concentrations the triterpene glycosides showed mitogenic activity and modulated the immune response. The similarity in the action of the glycosides was first of all observed with respect to the dose-dependent duality of their effects i.e. the diametrically opposite action of the high and low doses. The expression of the effects was likely determined by the chemical structure of the triterpene glycosides. Liberation of the soluble mediators served as a secondary signal to the clonal expansion and differentiation of the cells.


Assuntos
Adjuvantes Imunológicos/farmacologia , Glicosídeos/farmacologia , Toxinas Marinhas/farmacologia , Triterpenos/farmacologia , Linfócitos B/efeitos dos fármacos , Células Cultivadas , Glicosídeos/química , Mitógenos/farmacologia , Estrutura Molecular , Baço/citologia , Baço/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Triterpenos/química
9.
Antibiot Khimioter ; 34(11): 831-3, 1989 Nov.
Artigo em Russo | MEDLINE | ID: mdl-2633697

RESUMO

The effect of triterpene glycosides synthesized on the basis of betulafolientriol, ginsenoside Rb1 from gingseng, betulafolientriol and its 3-epimer on the growth of the Ehrlich tumor cell cultures was studied. It was shown that, in relation to the quantitative composition and sites of carbohydrate residue linkage to aglycone as well as configuration of the alpha- or beta-hydroxyl group at C-3, the activity of the triterpenoids of the dammaranic series changed within wide ranges. 3- and 12-0-beta-D-glycosides of 3-epibetulafolientriol proved to be the most active.


Assuntos
Carcinoma de Ehrlich/patologia , Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Árvores , Triterpenos/farmacologia , Animais , Antineoplásicos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Fenômenos Químicos , Química , Meios de Cultura , Técnicas In Vitro
11.
Bioorg Khim ; 10(5): 666-9, 1984 May.
Artigo em Russo | MEDLINE | ID: mdl-6093818

RESUMO

Transformed steroids having oxidized side chains in the D ring site and varying by polarity of the substituent at the ring A C(3)-position--acetates, glucosides or with free hydroxyls--in the concentration range 1 X 10(-4) - 1 X 10(-7) M were found to inhibit Na+, K+-ATPase. The extent of inhibition decreases with the rise in the polarity of the A region of the steroid molecule. With the compound devoid of polar groups in the D region an increase in the inhibitory activity is observed on passing from 3-acetate to 3-glucoside. The data obtained confirm the relationship between the extent of Na+, K+-ATPase inhibition and biphilicity of the molecule.


Assuntos
Glicosídeos Cardíacos/farmacologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Esteroides/farmacologia , Técnicas In Vitro , Oxirredução , Relação Estrutura-Atividade
12.
Biol Bull Acad Sci USSR ; 6(4): 464-8, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-549682

RESUMO

Antifungal activity was tested in 49 pentacyclic triterpenoids and their glycosides, of plant and semisynthetic origin. Several of these compounds inhibited the multiplication of the yeast Saccharomyces carlsbergensis. The highest antifungal activity was found in the triterpene glycosides oleanolic acid and hederagenin, which have a free carboxyl group at C 28(27). Triterpenes of the meristotropic acid, macedonic acid, and lupan types had no fungistatic activity at concentrations up to 100 microgram/ml.


Assuntos
Antifúngicos , Saccharomyces/efeitos dos fármacos , Triterpenos/farmacologia , Antifúngicos/isolamento & purificação , Fenômenos Químicos , Química , Glicosídeos/farmacologia , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Plantas/análise , Relação Estrutura-Atividade , Triterpenos/isolamento & purificação
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