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1.
Nat Prod Res ; 34(2): 311-316, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30404547

RESUMO

Development of a novel agent for control of schistosomiasis is a mandate. In-vitro anti-schistosomal activity of the aerial parts of Huernia saudi-arabica were examined. Chromatographic investigations of the ethanol extract (EE) were afforded three compounds. Pregnane glycoside (CI) 12-ß-p-hydroxy-benzoyl-20-O-acetyl-boucerin-3-O-ß-D-glucopyranosyl-(1→4)-ß-D-cymaropyranosyl-(1→4)-ß-D-cymaropyranoside, in addition to two flavonoids (CII) luteolin-4'-O-ß-D-neohesperidoside and (CIII)quercetin-3-rutinoside were recognized via spectral analysis. The schistosomicidal effects were evaluated using scanning electron microscope (SEM). In-vitro bioassays on the viability (mobility, morphological changes and mortality) of Schistosoma mansoni adults, cercariae, miracidia and eggs at different concentrations 2.5, 5, 12.5, 25 and 50 µg/ml of EE and 2.6, 5.2, 13, 26 and 52 µM of CI in incubation times 1,2,4,6,12hrs were carried out. EE and CI evidenced in-vitro anti-schistosomal activity with a dose and incubation time-dependent fashion. The effect of EE and CI was evident by the topography damage showed by SEM. EE proved moderate in-vitro cytotoxicity with IC50 of 8.48 µg/ml.


Assuntos
Apocynaceae/química , Glicosídeos/farmacologia , Pregnanos/farmacologia , Esquistossomicidas/isolamento & purificação , Animais , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glicosídeos/isolamento & purificação , Extratos Vegetais/química , Pregnanos/isolamento & purificação , Schistosoma mansoni/efeitos dos fármacos , Esquistossomicidas/farmacologia
2.
Phytochemistry ; 168: 112127, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31550672

RESUMO

Five undescribed C21 pregnane glycosides, epigycosides D-H, together with four known analogues, two lignans, and a flavonoid have been isolated from the stems of Epigynum cochinchinensis. The structures of pregnane glycosides were elucidated using spectroscopic techniques and acid hydrolysis. The in vitro immunological activities were assessed against Con A-stimulated proliferation of mice splenocytes. The C21 pregnane glycosides showed immunosuppressive activity in a concentration-dependent manner. Moreover, epigycoside E exhibited a potent immunosuppressive effect, and the IC50 value on Con A-stimulated mice splenocytes was 22.1 ±â€¯6.4 µM. Epigycoside E also caused G0/G1 arrest, and inhibited TNF-α and IL-2 production.


Assuntos
Apocynaceae/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Imunossupressores/isolamento & purificação , Imunossupressores/farmacologia , Pregnanos/isolamento & purificação , Pregnanos/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Animais , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Concanavalina A/antagonistas & inibidores , Concanavalina A/farmacologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Glicosídeos/química , Imunossupressores/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Caules de Planta/química , Pregnanos/química , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos
3.
Nat Prod Res ; 33(13): 1885-1890, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29865893

RESUMO

A new pregnane steroid, named aspergillon A (1), together with two known compounds, (22E,24R)-ergosta-5,7,22-trien-3ß-ol (2) and (22E, 24R)-ergosta-4,6,8(14),22-tetraen-3-one (3) were isolated from cultures of the tin mine tailings-associated fungus Aspergillus versicolor. The new structure and absolute configuration were determined with the help of extensive spectroscopic analyses and quantum chemical calculations of the electronic circular dichroism (ECD) spectra.


Assuntos
Aspergillus/química , Pregnanos/isolamento & purificação , Esteroides/isolamento & purificação , Dicroísmo Circular , Fungos , Mineração , Estrutura Molecular , Pregnanos/química , Análise Espectral , Esteroides/química
4.
Nat Prod Res ; 33(22): 3210-3214, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29726713

RESUMO

Phytochemical investigation on the ethyl acetate fraction of the leaves of Epigynum cochinchinensis led to the isolation of a new C21 pregnane glycoside, epigycoside B (1), together with three known analogues. Their structures were elucidated on the basis of extensive spectroscopic techniques, including UV, MS, and NMR experiments, as well as the chemical methods. Compound 1 displayed in vitro immunosuppressive activity against concanavalin A (Con A)/Lipopolysaccharides (LPS)-stimulated proliferation of mice splenocyte. The activity was significant as compared with control group at 50 µM concentration.


Assuntos
Apocynaceae/química , Glicosídeos/farmacologia , Imunossupressores/isolamento & purificação , Pregnanos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Concanavalina A/efeitos dos fármacos , Glicosídeos/química , Glicosídeos/imunologia , Glicosídeos/isolamento & purificação , Imunossupressores/química , Imunossupressores/farmacologia , Lipopolissacarídeos , Camundongos , Estrutura Molecular , Folhas de Planta/química , Pregnanos/química , Pregnanos/imunologia , Pregnanos/isolamento & purificação , Análise Espectral , Baço/citologia
5.
J Agric Food Chem ; 66(29): 7735-7739, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29965760

RESUMO

To investigate the sweet-tasting components in the roots of Myriopteron extensum, the phytochemical study of its roots was conducted, which led to the discovery of 12 new C21 pregnane glycosides (extensumside M-X, 1-12) and two known ones (extensumside C and extensumside E, 13-14). Their chemical structure elucidation was accomplished by means of spectroscopic methods: IR, UV, ESI-MS, and NMR (1H NMR, 13C NMR, HSQC, 1H-1H COSY, HMBC, HSQC-TOCSY, and ROESY), as well as the chemical evidence. Sensory analysis of these compounds revealed that nine of them (1, 3, 4, 5, 6, 7, 8, 13, and 14) are highly sweet-tasting compounds. Their sweetness intensities are 25 to 400 times greater than that of sucrose. Analysis of the structure-activity relationship (SAR) indicated that the sweet intensities of the isolated compounds are closely related to the aglycone 3ß,16α-dihydroxy-pregn-5-en-20-one, the number and type of the monosaccharide in the sugar chain linked to C-3 and C-16 and the position of the mBe group.


Assuntos
Apocynaceae/química , Glicosídeos/química , Extratos Vegetais/química , Pregnanos/química , Edulcorantes/química , Glicosídeos/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Pregnanos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Edulcorantes/isolamento & purificação , Paladar
6.
Phytochemistry ; 150: 75-84, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29567513

RESUMO

Eight adonilide (14,20α-epoxy-3ß,20-dihydroxy-14ß-pregn-5-en-18-oic acid γ-lactone) glycosides, named aestivalosides A-H, and four glycosides of the adonilide derivatives, named aestivalosides I-L, were isolated from the MeOH extract of seeds of Adonis aestivalis. Aestivalosides A-L were previously undescribed compounds, and were structurally characterized using spectroscopic techniques, including two-dimensional NMR, and chemical methods.


Assuntos
Adonis/química , Glicosídeos/isolamento & purificação , Pregnanos/isolamento & purificação , Sementes/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Pregnanos/química
7.
Bioorg Med Chem Lett ; 28(7): 1252-1256, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29526485

RESUMO

Bioassay-guided fractionation of the methanolic extract from the roots of Cynanchum atratum has resulted in the isolation of three new pregnane glycosides (1-3) along with four known compounds (4-7). Their structures were identified by analysis of the spectroscopic data including extensive 2D NMR. All of the isolates were evaluated for their potential to inhibit the melanin production in α-melanocyte stimulating hormone (α-MSH)-activated B16 melanoma cells. Of these, compounds 4-7 dose-dependently inhibited the melanin production with the IC50 values ranging from 4 µM to 33 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cynanchum/química , Glicosídeos/farmacologia , Melaninas/antagonistas & inibidores , Melanoma Experimental/tratamento farmacológico , Extratos Vegetais/farmacologia , Pregnanos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Melaninas/biossíntese , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Pregnanos/química , Pregnanos/isolamento & purificação , Relação Estrutura-Atividade
8.
Phytochemistry ; 147: 147-157, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29331903

RESUMO

Dregea sinensis Hemsl is an important herbal medicine in the Dai nationality of China. Its prominent clinical application has generated interest in the polyoxypregnane glycosides of the plant. This paper describes an extension of previous research on the polyoxypregnane di- and triglycosides of D. sinensis, aiming at identifying related tetraglycosides. On the basis of HPLC-ESI-MSn analysis in positive mode, twenty-five previously undescribed polyoxypregnane tetraglycosides were characterized (regarding molecular masses and fragmentation in MSn) from an ethyl acetate fraction that was not previously investigated. Guided by MSn fragmentation and known structures of related di- and triglycosides from D. sinensis, tentative structures were predicted from the MS data. In order to test the predictions, eight of the glycosides were isolated and their structures were elucidated by 1D and 2D NMR methods, confirming the tentative predictions. Finally, the cytotoxicity of the isolates was evaluated on several human cell lines with little effect in general, even though slight inhibitory effects of four polyoxypregnane glycosides were detected at 10 µM against the human leukemia cell line HL-60.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apocynaceae/química , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Pregnanos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , China , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Medicina Tradicional Chinesa , Estrutura Molecular , Pregnanos/isolamento & purificação , Pregnanos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
9.
J Nat Med ; 72(1): 347-356, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29177792

RESUMO

Previously, phytochemical investigation of the roots of Asclepias tuberosa (Asclepiadaceae) led to the isolation of some 8,12;8,20-diepoxy-8,14-secopregnane tri-, tetra-, and penta-glycosides. An additional eight new minor 8,12;8,20-diepoxy-8,14-secopregnane glycosides were afforded in the recent investigation of this plant. These glycosides consisted of six or seven 2,6-dideoxy-hexopyranoses together with the aglycone, tuberogenin. The structures of each of these compounds were established using NMR, mass spectroscopic analysis and chemical evidence. As 8,12;8,20-diepoxy-8,14-secopregnane-type glycosides were observed only in A. tuberosa, these compounds were considered to be characteristic phytochemicals of this plant.


Assuntos
Asclepias/química , Glicosídeos/isolamento & purificação , Raízes de Plantas/química , Pregnanos/isolamento & purificação , Configuração de Carboidratos , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Pregnanos/química
10.
Nat Prod Res ; 32(24): 2882-2886, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29034743

RESUMO

Gongronema latifolium Benth (Asclepiadaceae) is an edible-green-leafy vegetable with known medicinal value. A chemical investigation of the 80% methanolic extract of the leaves led to the isolation of a new pregnane glycoside: iloneoside (3-O-[6-deoxy-3-O-methyl-ß-D-allopyranosyl-(1→14)-ß-D-oleandropyranosyl]-11,12-di-O-tigloyl-17ß-marsdenin), together with four known constituents. Their chemical structures were determined by spectroscopic analysis. The isolates were tested for their in vitro growth inhibitory activity against human leukemia HL-60 cells. Iloneoside was the most active and gave apoptotic response. Molecular docking analysis demonstrated that iloneoside could be accommodated within hot spots of anti-apoptotic protein Bcl-2. These results suggest G. latifolium as a reliable source of potent anticancer compounds.


Assuntos
Antineoplásicos/isolamento & purificação , Apocynaceae/química , Glicosídeos/isolamento & purificação , Folhas de Planta/química , Pregnanos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células HL-60/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Extratos Vegetais/química
11.
J Nat Prod ; 80(6): 1714-1724, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28561586

RESUMO

Five 12,20-epoxypregnane glycosides (1-3, 5, and 6) and two 11,12-seco-pregnane glycosides (4 and 7) with spirodilactone motifs, as well as spirodilactone cleavage products 8 and 9, were isolated from the stems of Hoya kerrii. The relative configurations of the three related skeletons were supported by ROESY experiments and X-ray crystallographic analyses. The isolates were evaluated for their anti-inflammatory activity based on the inhibition of NO production in RAW264.7 cells, and some showed IC50 values ranging from 12.6 to 96.5 µM. The most potent compound, 9a, was also examined for its anti-inflammatory mechanism against mRNA expression and was found to down-regulate mRNA expression of iNOS and COX-2 in a dose-dependent manner.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Apocynaceae/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Pregnanos/isolamento & purificação , Pregnanos/farmacologia , Animais , Anti-Inflamatórios/química , Cristalografia por Raios X , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Glicosídeos/química , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química , Pregnanos/química , Tailândia
12.
Steroids ; 125: 27-32, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28636871

RESUMO

Five new pregnane-type steroidal glycosides, named menarandrosides A-E (1-2, 5-7) were isolated from the aerial parts of Cynanchum menarandrense, together with three known compounds, carumbelloside I (3), carumbelloside II (4), and pregnenolone-3-O-gentiobioside (8). Their structures were determined on the basis of spectroscopic analyses including NMR and mass spectrometry, reporting C-21 steroids glycosylated only by one or two glucose moieties. Compounds were then investigated for their potential to stimulate glucagon-like peptide-1 (GLP-1) secretion in intestinal cells; although none of the pure compounds had any influence, the fraction enriched in pregnanes exhibited a significant activity, suggesting a possible synergistic effect. Furthermore, none of the purified compounds affected cell viability.


Assuntos
Cynanchum/química , Glicosídeos/química , Glicosídeos/farmacologia , Pregnanos/química , Pregnanos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glicosídeos/isolamento & purificação , Intestinos/citologia , Pregnanos/isolamento & purificação
13.
Bioorg Med Chem Lett ; 27(12): 2736-2741, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28456553

RESUMO

An unprecedented spinaceamine-bearing pregnane namely scleronine (1) was isolated from a Chinese soft coral Scleronephthya sp. Its structure was determined on the basis of 1D and 2D NMR spectroscopic analyses in association with the HRESIMS data, while the absolute configurations were deduced by the single-crystal X-ray diffraction analysis. In addition, a dehydrogenated analogue (3) was synthesized through six steps with pregna-1,20-dien-3-one (2) as a precursor. The significantly inhibitory effects of 1 and 3 against the migration of tumor cells A549 and B16 accompanying the down-regulation of key genes (TGFß, TNFα, IL-1ß, and IL-6) were observed. These findings suggested that both 1 and 3 are potential for therapeutic usage aiming at cancer metastasis inhibition.


Assuntos
Antozoários/química , Compostos Heterocíclicos com 2 Anéis/farmacologia , Pregnanos/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Compostos Heterocíclicos com 2 Anéis/química , Compostos Heterocíclicos com 2 Anéis/isolamento & purificação , Humanos , Estrutura Molecular , Pregnanos/química , Pregnanos/isolamento & purificação , Teoria Quântica , Relação Estrutura-Atividade
14.
Nat Prod Res ; 31(20): 2435-2440, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28480737

RESUMO

Six pregnane steroids including one new compound namely 15ß-hydroxypregna-4,20-dien-3-one (1), were isolated and structurally elucidated from the octocoral Carijoa riisei. The cytotoxic activity against a panel of eight human cancer cell lines of isolated compounds was also evaluated by SRB method. As the results, 18-acetoxypregna-1,4,20-trien-3-one (5) showed significant cytotoxicity against all the tested cell lines with the IC50 values from 22.29 ± 1.47 to 48.73 ± 3.93 µM, whereas 15ß-acetoxypregna-1,4,20-trien-3-one (3) and 20R-acetoxypregna-1,4-dien-3-one (6) only exhibited weak effect on KB cell line with IC50 values of 93.62 ± 7.32 and 71.38 ± 5.45 µM, respectively.


Assuntos
17-alfa-Hidroxipregnenolona/isolamento & purificação , Antozoários/química , Pregnanos/química , Esteroides/química , 17-alfa-Hidroxipregnenolona/química , Animais , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Pregnanos/isolamento & purificação , Esteroides/isolamento & purificação , Vietnã
15.
J Ethnopharmacol ; 203: 110-119, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28363522

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Multidrug resistance (MDR) of cancer is often associated with the overexpression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (P-gp), multidrug resistance-associated protein-1 (MRP-1) and breast cancer resistance protein (BCRP or ABCG2), in cancer cells, which facilitates the active efflux of a wide variety of chemotherapeutic drugs out of the cells. Marsdenia tenacissima is a traditional Chinese medicinal herb that has long been clinically used for treatment of cancers, particularly in combinational use with anticancer drugs. Polyoxypregnanes (POPs) are identified as main constituents of this herb, and three of them have been reported to exhibit P-gp modulatory effect and thus reverse MDR. Therefore, it is of great necessity to investigate more POPs that have potential to reverse transporters-mediated MDR. AIM OF THE STUDY: We aimed to identify POPs as the chemical basis responsible for circumventing ABC transporters-mediated MDR by M. tenacissima. MATERIALS AND METHODS: The MDR reversal effects of M. tenacissima crude extract together with a series of isolated POPs were evaluated on several MDR cancer cell lines that overexpress P-gp, MRP1 or ABCG2. The activities of P-gp, MRP1 and ABCG2 were determined by the flow cytometry-based substrate efflux assay. Molecular docking of POPs to a three-dimensional human P-gp homology structure was also performed. RESULTS: The crude extract of M. tenacissima was firstly found to circumvent P-gp-mediated MDR. Then, 11 polyoxypregnane compounds (POPs) isolated from this herb were found to overcome P-gp-, MRP1- and/or ABCG2-mediated MDR. Further mechanistic study delineated that the reversal of MDR by these POPs was due to significant increase in the intracellular concentrations of the substrate anticancer drugs via their inhibition of different ABC transporter-mediated efflux activities. Furthermore, molecular docking revealed that POPs with P-gp modulatory effect bound to P-gp and fitted well into the cavity between the alpha and beta subunit of P-gp via forming hydrogen bonds. In addition, several key structural determinants for inhibition of P-gp, MRP1 or ABCG2 by POPs were illustrated. CONCLUSIONS: Our findings advocated the rational use of M. tenacissima to enhance efficacies of conventional anticancer drugs in tumors with ABC drug transporters-mediated MDR. Furthermore, 11 POPs were found to contribute to MDR reversal effect of M. tenacissima via inhibition of different ABC efflux transporters.


Assuntos
Antineoplásicos/farmacologia , Marsdenia/química , Extratos Vegetais/farmacologia , Pregnanos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Simulação de Acoplamento Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Pregnanos/isolamento & purificação
16.
Nat Prod Res ; 31(24): 2893-2899, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28361559

RESUMO

Chemical investigation on the aqueous fraction of the stems of Epigynum cochinchinensis led to the isolation of a new pregnane glycoside named as epigycoside A (1) along with three known analogues (2-4). The structure of compound 1 was elucidated by means of spectroscopic techniques, including HRESIMS, and 1D and 2D NMR experiments. The immunosuppressive activity of 1 was evaluated by an in vitro model of concanavalin A-induced mice splenocytes proliferation. Compound 1 showed significant inhibitory activity in a dose-dependent manner, closer to the efficacy of positive control, dexamethasone, at a concentration of 50 µM.


Assuntos
Apocynaceae/química , Glicosídeos/isolamento & purificação , Imunossupressores/isolamento & purificação , Imunossupressores/farmacologia , Pregnanos/isolamento & purificação , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Glicosídeos/química , Glicosídeos/farmacologia , Imunossupressores/química , Camundongos , Estrutura Molecular , Caules de Planta/química , Pregnanos/química , Pregnanos/farmacologia , Baço/citologia
17.
J Asian Nat Prod Res ; 19(6): 557-563, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28446029

RESUMO

Two new sugar-free 14,15-secopregnane-type steroids, 14-O-methyl-3-epi-hirundigenin (1) and 2-deoxyamplexicogenin A (2), along with two known sugar-free pregnane-type steroids, were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of the new compounds were characterized on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR methods, albeit the MS experiments did not display the molecular ion peaks. Compound 2 was the aglycones of stauntosides J and K, etc., previously isolated from C. stauntonii. The isolation and identification of the new compounds graced the structural diversity of pregnane-type steroids from C. stauntonii.


Assuntos
Cynanchum/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Raízes de Plantas/química , Pregnanos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pregnanos/química
18.
Fitoterapia ; 118: 107-111, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28300701

RESUMO

Phytochemical investigation on the leaves of Epigynum auritum led to the isolation of three novel C21 pregnane glycosides, epigynosides, E-G (1-3), together with two known pregnane glycosides, epigynosides A (4) and C (5). Their structures were elucidated based on extensive spectroscopic data (MS, IR, 1D and 2D NMR) analysis, as well as comparison with the reported data. The immunological activities of the new compounds was evaluated against concanavalin A (Con A)-stimulated proliferation of mice splenocyte in vitro. Compounds 1-3 displayed significant immunosuppressive activities, close to the efficacy of the positive control (dexamethasone) at the concentration of 50µM.


Assuntos
Apocynaceae/química , Glicosídeos/química , Imunossupressores/química , Pregnanos/química , Baço/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Células Cultivadas , Glicosídeos/isolamento & purificação , Humanos , Imunossupressores/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Folhas de Planta/química , Pregnanos/isolamento & purificação , Baço/citologia
19.
Phytochemistry ; 138: 152-162, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28284564

RESUMO

Nine 14,15-secopregnane-type C21-steriosides, stauntosides U, V, V1-V3, W and C1-C3, as well as two known C21-steriosides, were isolated from the roots of Cynanchum stauntonii. Stauntosides U, V and V1-V3 share the same basic structural features of 8α:14α,14:16,15:20,18:20-tetraepoxy-14,15-secopregn-6-ene-3ß,5α,9α-triol, with the numbering system following that of C21-pregnanes. The aglycones of stauntosides U, V and V1-V3 are classified into two subcategories, the 5,9-dihydroxy groups and 5α:9α-peroxy bridge, according to the oxidative states of the two hydroxy groups at the C-5 and C-9 positions. The anti-inflammatory activity of the major compounds was assessed in an in vitro inflammatory model of mouse peritoneal macrophages using IC50 values of the inhibition of nitric oxide (NO) production as an indicator. Stauntosides V1 and V3 exhibited target activity with IC50 values of 9.3 µM and 12.4 µM, respectively, compared with dexamethasone, which was used as a positive control.


Assuntos
Cynanchum/química , Raízes de Plantas/química , Pregnanos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Óxido Nítrico/metabolismo , Pregnanos/isolamento & purificação
20.
J Nat Prod ; 80(4): 1102-1109, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28294615

RESUMO

Further phytochemical investigation of the root bark of Periploca sepium afforded nine new spiro-orthoester group-containing pregnane-type glycosides termed periplosides O-V and 3-O-formyl-periploside A. The structures of these glycosides along with the absolute configuration of the unique seven-membered formyl acetal-bridged spiro-orthoester function and the 4,6-dideoxy-3-O-methyl-Δ3-2-hexosulosyl moiety were elucidated on the basis of spectroscopic data interpretation and chemical transformation. The absolute configurations of the major compounds periplosides C and F were established by single-crystal X-ray diffraction analysis. The isolated compounds were evaluated for their inhibitory activities against the proliferation of T-lymphocytes. As a result, periploside C, the most abundant glycoside containing a spiro-orthoester moiety found in the plant, exhibited the most favorite selective index value (SI = 82.5). The length and constitution of the saccharide chain in the periplosides were found to influence the inhibitory activity and the SI value.


Assuntos
Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Imunossupressores/isolamento & purificação , Imunossupressores/farmacologia , Periploca/química , Pregnanos/isolamento & purificação , Pregnanos/farmacologia , Proliferação de Células/efeitos dos fármacos , Glicosídeos/química , Imunossupressores/química , Estrutura Molecular , Raízes de Plantas/química , Pregnanos/química , Linfócitos T/efeitos dos fármacos
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