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1.
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
2.
Nat Commun ; 10(1): 3378, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358750

RESUMO

Steroidal C19-hydroxylation is pivotal to the synthesis of naturally occurring bioactive C19-OH steroids and 19-norsteroidal pharmaceuticals. However, realizing this transformation is proved to be challenging through either chemical or biological synthesis. Herein, we report a highly efficient method to synthesize 19-OH-cortexolone in 80% efficiency at the multi-gram scale. The obtained C19-OH-cortexolone can be readily transformed to various synthetically useful intermediates including the industrially valuable 19-OH-androstenedione, which can serve as a basis for synthesis of C19-functionalized steroids as well as 19-nor steroidal drugs. Using this biocatalytic C19-hydroxylation method, the unified synthesis of six C19-hydroxylated pregnanes is achieved in just 4 to 9 steps. In addition, the structure of sclerosteroid B is revised on the basis of our synthesis.


Assuntos
Androstenodiona/química , Cortodoxona/química , Pregnanos/química , Esteroides/química , Androstenodiona/metabolismo , Biocatálise , Cortodoxona/metabolismo , Hidroxilação , Modelos Químicos , Estrutura Molecular , Pregnanos/metabolismo , Esteroides/síntese química , Esteroides/metabolismo
3.
Steroids ; 148: 28-35, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31075339

RESUMO

20R-Hydroxy short-chain ecdysteroids were synthesized by chemo- and stereoselective reduction of poststerone acetonide with L-Selectride or LiAlH4. The same reaction with the excess of L- Selectride followed by the treatment of the reaction mixture with hydrochloric acid is accompanied by (8R)-13(14 → 8)abeo- rearrangements, which resulted in the contraction/expansion of C/D pregnane rings. The reaction of 20R-hydroxy poststerone analogs with (diethylamino)sulfur trifluoride (DAST) proceeds through intramolecular rearrangements and provides D-homo- or 13,14-seco- androstane structures.


Assuntos
Androstanos/síntese química , Ecdisterona/química , Pregnanos/síntese química , Esteroides/química , Androstanos/química , Conformação Molecular , Pregnanos/química , Teoria Quântica , Estereoisomerismo , Termodinâmica
4.
Chem Biodivers ; 16(6): e1900062, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30983116

RESUMO

Seven new polyhydroxypregnane glycosides, named cynotophyllosides P-V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid. Their structures were elucidated by a variety of spectroscopic techniques, as well as acid-catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A- and LPS-induced proliferation of mice splenocytes. Immunoenhancing (for 1, 9) and immunosuppressive (for 2) activities were observed. Furthermore, cynotophylloside R (3) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 µg/ml.


Assuntos
Cynanchum/química , Glicosídeos/química , Pregnanos/química , Animais , Proliferação de Células/efeitos dos fármacos , Cynanchum/metabolismo , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo
5.
J Enzyme Inhib Med Chem ; 34(1): 684-691, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30777494

RESUMO

Synthetic progesterone and 5α/ß-pregnane-3,20-dione derivatives were evaluated as in vitro and in vivo modulators of multidrug-resistance (MDR) using two P-gp-expressing human cell lines, the non-steroidogenic K562/R7 erythroleukaemia cells and the steroidogenic NCI-H295R adrenocortical carcinoma cells, both resistant to doxorubicin. The maximal effect in both cell lines was observed for 7α-O-benzoyloxy,11α(R)-O-tetrahydropyranyloxy-5ß-pregnane-3,20-dione 4. This modulator co-injected with doxorubicin significantly decreased the tumour size and increased the survival time of immunodeficient mice xenografted with NCI-H295R or K562/R7 cells.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pregnanos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos SCID , Conformação Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Pregnanos/síntese química , Pregnanos/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
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
7.
Nat Prod Res ; 33(11): 1570-1576, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29334245

RESUMO

A new polyhydroxylated pregnane, named lß,2ß,3ß,4ß,5ß,6ß-hexolhydroxy-pregn-16-en-20-one (1), along with nine known (2-10) steroidal saponins were isolated from the whole plant of Reineckia carnea. Structure elucidations of all compounds were established by interpretation of their NMR spectral data, HR-ESI-MS and comparing with literatures. In addition, these compounds were evaluated with anticomplement activity. The result showed that compound 1 exhibited anticomplement effects with the CH50 values of 0.043 mg/mL, but saponins (2-10) showed no inhibition. Interestingly, hydrolysis of steroidal saponins (2-10) resulted in its aglycones (2a-10a) correspondingly which showed anticomplement activity with the CH50 values of 0.049-0.156 mg/mL.


Assuntos
Asparagaceae/química , Inativadores do Complemento/farmacologia , Esteroides/química , Esteroides/farmacologia , Animais , Inativadores do Complemento/química , Avaliação Pré-Clínica de Medicamentos/métodos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Cobaias , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pregnanos/química , Pregnanos/farmacologia , Saponinas/química , Saponinas/farmacologia , Ovinos , Espectrometria de Massas por Ionização por Electrospray
8.
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
9.
J Nat Med ; 73(1): 93-103, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30251034

RESUMO

Seven new pregnane glycosides (1-7) and eight known compounds (8-15) were isolated from the bark of Marsdenia cundurango (Asclepiadaceae). The structures of 1-7 were determined by spectroscopic analysis, including two-dimension NMR spectroscopy, chemical transformations, and chromatographic analysis of the hydrolyzed products. The isolated compounds 1-15 were evaluated for their cytotoxic activity against HL-60 human leukemia cells, A549 human lung adenocarcinoma cells, and TIG-3 normal human lung cells, including apoptosis-inducing activity of a representative pregnane glycoside in HL-60 cells.


Assuntos
Citotoxinas/uso terapêutico , Glicosídeos/química , Células HL-60/metabolismo , Marsdenia/química , Casca de Planta/química , Pregnanos/química , Citotoxinas/farmacologia , Humanos
10.
Theriogenology ; 122: 130-136, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30265893

RESUMO

The objectives of this study were to compare via liquid chromatography-tandem mass spectrometry (LC-MS/MS) progesterone (P4), 5α-dihydroprogesterone (DHP), allopregnanolone, 3ß-hydroxy-5α-pregnan-20-one (3ß5P), 20α-hydroxy-5α-pregnan-3-one (20α5P), 5α-pregnan-3ß,20α-diol (ßα-diol), and 5α-pregnan-3ß,20ß-diol (ßß-diol) concentrations in plasma of mares with experimentally-induced, ascending placentitis compared to gestationally age-matched control mares. Placentitis was induced via intracervical inoculation of Streptococcus equi spp. zooepidemicus between 260 and 280 days of gestation. Placentitis mares were subdivided into those which aborted in less than eight days (n = 6; acute) and those that aborted at ≥ 8 days after inoculation (n = 9; chronic). Ten pregnant mares at similar gestational ages served as healthy controls. Pregnanes were measured for days (-8), -6, -4, -3, -2, -1, and 0 days preceding abortion in the treated mares, and for the matched days of gestation in the control mares by LC-MS/MS and by immunoassay for immunoreactive (ir) P4. In mares with chronic placentitis, concentrations of DHP and its downstream metabolites (allopregnanolone, 3ß5P, 20α5P, ßα-diol) increased at 2-8 days prior to abortion compared to control mares. Of these pregnanes, 20α5P and ßα-diol increased at eight days prior to abortion and demonstrated the largest increase (approximately 3 to 4×) in mares with chronic placentitis compared to control mares. Concentrations of P4 determined by LC-MS/MS were at or below the limit of detection (0.5 ng/mL) for control mares and did not increase significantly in mares with chronic placentitis. Immunoreactive-P4 was increased at two days prior to abortion in mares with chronic placentitis but was not different from controls in mares with acute placentitis. In mares with acute placentitis, concentrations of DHP, allopregnanolone, 3ß5P, 20α5P, and ßα-diol decreased within 0-3 days prior to abortion. In mares with chronic placentitis, the patterns of increased pregnanes metabolized by the placenta was similar to changes in maternal pregnanes noted in normal mares beyond Day 300 of gestation and likely represent the effects of fetal stress and adrenal activation on pregnane metabolism by the fetus and placenta. Decreases in these same pregnanes in mares with acute cases likely reflect extreme fetal or placental compromise.


Assuntos
Doenças dos Cavalos/metabolismo , Doenças Placentárias/veterinária , Pregnanos/sangue , Animais , Cromatografia Líquida/veterinária , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Doenças Placentárias/metabolismo , Doenças Placentárias/microbiologia , Gravidez , Pregnanos/química , Streptococcus equi , Espectrometria de Massas em Tandem/veterinária
11.
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
12.
Nat Commun ; 9(1): 1838, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743477

RESUMO

Furanosteroids, represented by wortmannin, viridin, and demethoxyviridin, are a special group of fungal-derived, highly oxygenated steroids featured by an extra furan ring. They are well-known nanomolar-potency inhibitors of phosphatidylinositol 3-kinase and widely used in biological studies. Despite their importance, the biosyntheses of these molecules are poorly understood. Here, we report the identification of the biosynthetic gene cluster for demethoxyviridin, consisting of 19 genes, and among them 15 biosynthetic genes, including six cytochrome P450 monooxygenase genes, are deleted. As a result, 14 biosynthetic intermediates are isolated, and the biosynthetic pathway for demethoxyviridin is elucidated. Notably, the pregnane side-chain cleavage requires three enzymes: flavin-dependent Baeyer-Villiger monooxygenase, esterase, and dehydrogenase, in sharp contrast to the single cytochrome P450-mediated process in mammalian cells. Structure-activity analyses of these obtained biosynthetic intermediates reveal that the 3-keto group, the C1ß-OH, and the aromatic ring C are important for the inhibition of phosphatidylinositol 3-kinase.


Assuntos
Androstenos/metabolismo , Pregnanos/metabolismo , Xylariales/metabolismo , Androstenos/química , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Vias Biossintéticas , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Pregnanos/química , Xylariales/enzimologia , Xylariales/genética
13.
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
14.
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
15.
J Biol Chem ; 293(8): 3013-3027, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29301936

RESUMO

Neurosteroids are endogenous sterols that potentiate or inhibit pentameric ligand-gated ion channels (pLGICs) and can be effective anesthetics, analgesics, or anti-epileptic drugs. The complex effects of neurosteroids on pLGICs suggest the presence of multiple binding sites in these receptors. Here, using a series of novel neurosteroid-photolabeling reagents combined with top-down and middle-down mass spectrometry, we have determined the stoichiometry, sites, and orientation of binding for 3α,5α-pregnane neurosteroids in the Gloeobacter ligand-gated ion channel (GLIC), a prototypic pLGIC. The neurosteroid-based reagents photolabeled two sites per GLIC subunit, both within the transmembrane domain; one site was an intrasubunit site, and the other was located in the interface between subunits. By using reagents with photoreactive groups positioned throughout the neurosteroid backbone, we precisely map the orientation of neurosteroid binding within each site. Amino acid substitutions introduced at either site altered neurosteroid modulation of GLIC channel activity, demonstrating the functional role of both sites. These results provide a detailed molecular model of multisite neurosteroid modulation of GLIC, which may be applicable to other mammalian pLGICs.


Assuntos
Proteínas de Bactérias/metabolismo , Desoxicorticosterona/análogos & derivados , Canais Iônicos de Abertura Ativada por Ligante/metabolismo , Modelos Moleculares , Neurotransmissores/metabolismo , Pregnanos/metabolismo , Substituição de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Cianobactérias , Desoxicorticosterona/química , Desoxicorticosterona/metabolismo , Hidroxilação , Cinética , Canais Iônicos de Abertura Ativada por Ligante/química , Canais Iônicos de Abertura Ativada por Ligante/genética , Ligantes , Conformação Molecular , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Neurotransmissores/química , Marcadores de Fotoafinidade/química , Mutação Puntual , Pregnanos/química , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
16.
Bioorg Med Chem Lett ; 28(3): 330-333, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29292227

RESUMO

Phytochemical investigation of the root barks of Periploca chrysantha D. S. Yao, X. C. Chen et J. W. Ren (Asclepiadaceae) led to the elucidation of four new spiroorthoester group-containing pregnane glycosides (1-4), named periplosides W-Y and 3-O-formyl-periploside F. Their structures were elucidated on the basis of extensive spectroscopic analysis. The four new pregnane glycosides (1-4) were found to exhibit significantly inhibitory activities against the proliferation of B and T lymphocytes and favorable selective index comparable to those of cyclosporin A.


Assuntos
Linfócitos B/efeitos dos fármacos , Glicosídeos/farmacologia , Periploca/química , Casca de Planta/química , Raízes de Plantas/química , Pregnanos/farmacologia , Compostos de Espiro/farmacologia , Linfócitos T/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glicosídeos/química , Humanos , Conformação Molecular , Pregnanos/química , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
17.
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
18.
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
19.
Nat Prod Res ; 32(3): 261-267, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28714348

RESUMO

Two new steroidal glycosides 1 and 2, along with three known ones (3-5), were isolated from the 95% ethanol extract of the roots of Cynanchum limprichtii Schltr. The structure of the new compounds was elucidated as 3-O-α-L-diginopyranosyl-(1→4)-ß-D-digitoxopyranosyl-(1→4)-ß-D-cymaropyranosyl-(1→4)-ß-D-thevetopyranosyl-14, 16:15, 20:18, 20-triepoxy-14, 15-secopregn-4, 6, 8 (14)-triene (1) and 3-O-α-L-cymaropyranosyl-(1→4)-ß-D-digitoxopyranosyl- (1→4)-ß-D-3-demethyl-2-deoxythevetopyranosyl-14, 16: 15, 20: 8, 20-triepoxy-14, 15-secopregn-5, 8 (14)-diene (2) on the basis of spectroscopic analysis together with acidic hydrolysis. All compounds showed cytotoxic activity against the human cancer cell line HL60, with IC50 values of 55.36, 65.41, 17.88, 17.68 and 33.5 µM, respectively. While, only compound 3 showed cytotoxicity against the Caco-2 cell line, with an IC50 value of 67.47 µM.


Assuntos
Cynanchum/química , Glicosídeos/química , Raízes de Plantas/química , Pregnanos/química , Células CACO-2 , Glicosídeos/farmacologia , Células HL-60 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Pregnanos/farmacologia
20.
J Asian Nat Prod Res ; 20(12): 1101-1107, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28990798

RESUMO

A new highly oxygenated pregnane steroid, pregn-7-ene-2ß,3α,15α,20-tetrol (1) and two new 5-hydroxymethylfurfural derivatives, (5-formylfuran-2-yl)methyl 2-hydroxypropanoate (2) and (5-formylfuran-2-yl)methyl 2-(4-hydroxyphenyl)acetate (3), together with four known compounds, were isolated from the water decoction of Poria cocos. Their structures were established on the basis of extensive spectroscopic analysis. Compound 1 showed moderate inhibitory activity and a known compound (3S,6S)-3-[(1R)-1-hydroxyethyl]-6-(phenylmethyl)-2,5-piperazinedione (5) showed weak inhibitory activity against α-glucosidase, respectively.


Assuntos
Furaldeído/análogos & derivados , Furaldeído/química , Extratos Vegetais/química , Pregnanos/química , Wolfiporia/química , Estrutura Molecular
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