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1.
Molecules ; 22(1)2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28106795

RESUMO

The synthesis of polymers from renewable resources is a burning issue that is actively investigated. Polyepoxide networks constitute a major class of thermosetting polymers and are extensively used as coatings, electronic materials, adhesives. Owing to their outstanding mechanical and electrical properties, chemical resistance, adhesion, and minimal shrinkage after curing, they are used in structural applications as well. Most of these thermosets are industrially manufactured from bisphenol A (BPA), a substance that was initially synthesized as a chemical estrogen. The awareness on BPA toxicity combined with the limited availability and volatile cost of fossil resources and the non-recyclability of thermosets implies necessary changes in the field of epoxy networks. Thus, substitution of BPA has witnessed an increasing number of studies both from the academic and industrial sides. This review proposes to give an overview of the reported aromatic multifunctional epoxide building blocks synthesized from biomass or from molecules that could be obtained from transformed biomass. After a reminder of the main glycidylation routes and mechanisms and the recent knowledge on BPA toxicity and legal issues, this review will provide a brief description of the main natural sources of aromatic molecules. The different epoxy prepolymers will then be organized from simple, mono-aromatic di-epoxy, to mono-aromatic poly-epoxy, to di-aromatic di-epoxy compounds, and finally to derivatives possessing numerous aromatic rings and epoxy groups.


Assuntos
Produtos Biológicos/química , Compostos de Epóxi/síntese química , Resinas Epóxi/síntese química , Polímeros/síntese química , Compostos Benzidrílicos/química , Compostos Benzidrílicos/toxicidade , Produtos Biológicos/isolamento & purificação , Biomassa , Ácidos Cafeicos/química , Ácidos Cafeicos/isolamento & purificação , Cardanolídeos/química , Cardanolídeos/isolamento & purificação , Catecóis/química , Catecóis/isolamento & purificação , Química Verde , Lignina/química , Lignina/isolamento & purificação , Fenóis/química , Fenóis/toxicidade , Taninos/química , Taninos/isolamento & purificação , Temperatura , Terpenos/química , Terpenos/isolamento & purificação
2.
Clin Exp Pharmacol Physiol ; 38(5): 334-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21401694

RESUMO

1. Digitalis-like factors (DLFs) are believed to be involved in sodium metabolism via inhibition of Na(+) /K(+) -ATPase and may cause hypertension. Yet, the source and regulation of secretion of DLFs remain unknown. Recently, marinobufagenin (MBG) was isolated in mammals and implicated in renal sodium and water metabolism. More recently, we isolated marinobufotoxin (MBT), a suberoyl arginine ester of MBG, in Y-1 cells. We have developed an ELISA to measure MBG-like immunoreactivity (MBG-IR) and have characterized MBG-IR using chromatography. We have also identified a ouabain-like factor in cultured PC12 cells from a phaeochromocytoma cell line. In the present study, we examined whether MBT was produced in the adrenal medulla. 2. PC12 cells were cultured in serum-free medium and culture supernatants were collected over a period of 24 h. The supernatants were analysed by ELISA and HPLC to determine MBG-IR content. The HPLC fraction containing the main peak of MBG-IR was characterized by LC/MS. 3. Compared with samples collected at 0.5 h, the concentration of MBG-IR in culture supernatants increased significantly after 2 h and continued to increase until 24 h. The fraction with the highest ELISA peak for MBG-IR had the same HPLC elution time as authentic MBT. Furthermore, tandem mass spectrometry indicated that each fraction of MBT and MBG had the correct specific daughter ions. 4. The results indicate that MBT and MBG are produced and/or secreted by adrenomedullary cells.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Cardanolídeos/isolamento & purificação , Meios de Cultivo Condicionados/química , Feocromocitoma/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Animais , Cardanolídeos/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ensaio de Imunoadsorção Enzimática , Espectrometria de Massas , Células PC12 , Feocromocitoma/patologia , Ratos , Células Tumorais Cultivadas
3.
Chem Pharm Bull (Tokyo) ; 57(9): 948-56, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19721255

RESUMO

Naturally occurring constituents of biological or pharmaceutical interest often exist in the form of glycosides or conjugates. Mass spectral investigations of these compounds require soft ionization techniques if information on molecular mass, sugar sequence, or conjugate content is desired. In this study, matrix-assisted laser desorption/ionization (MALDI) quadrupole ion trap (QIT) time-of-flight tandem mass spectrometry (TOF-MS(n)) was used to identify both OSW-1, an acetylated cholestane diglycoside showing antitumor activity, and the cardiotonic steroid, bufotoxin. Each molecular-related ion was identified, and subsequent collision-induced dissociation experiments in which a molecular-related ion was selected as a precursor ion produced the characteristic product ions that are essential for structural elucidation. OSW-1 and its analogue with a modified side chain, thienyl OSW-1, were synthesized, and bufotoxins, i.e., marinobufotoxin and its homologue, marinobufagin 3-pimeloylarginine ester, were isolated from toad venom. On MALDI-TOF-MS, sodium-adduct [M+Na](+) ions were observed in the steroid glycosides, although protonated [M+H](+) ions were relatively more abundant than sodium-adduct [M+Na](+) ions in the bufotoxins. On the basis of tandem MS results, we propose key fragmentation pathways. The sugar moiety or side chain from the precursor ion was eliminated in OSW-1. However, characteristic product ions originating from the cleavage of the side chain with an ester formation were observed in the bufotoxins. Post-source decay (PSD) on MALDI-TOF-MS is also described when evaluating alpha-cyano-4-hydroxycinnamic acid or 2,5-dihydroxybenzoic acid as a matrix to obtain useful ions required for the identification of compound.


Assuntos
Antineoplásicos/química , Cardanolídeos/química , Colestenonas/química , Saponinas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Venenos de Anfíbios/química , Animais , Anuros , Cardanolídeos/isolamento & purificação
4.
Hypertension ; 49(1): 209-14, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17116763

RESUMO

Marinobufagenin and telecinobufagin have been identified as digitalis-like factors in mammals. In toads, marinobufagenin-related compounds, such as marinobufotoxin (MBT), have been isolated in some tissues but not in mammals, and its biological action has not been elucidated. Herein, we aimed to explore the possible production and/or secretion of MBT and the biological action in rats. First, the MBT in culture supernatant of the adrenocortical-originated cell line Y-1 was analyzed by high-performance liquid chromatography and sensitive ELISA for marinobufagenin-like immunoreactivity. Moreover, the structural information was obtained by mass spectrometry. To determine the biological action, MBT (9.6 and 0.96 microg/kg per day) was intraperitoneally infused via an osmotic minipump for 1 week. Blood pressure and renal excretion of marinobufagenin-like immunoreactivity were measured. Marinobufagenin-like immunoreactivity was found in Y-1 cell culture media, and the concentration increased until 24 hours. The structural analysis suggested that marinobufagenin-like immunoreactivities were marinobufagenin and MBT, and tandem mass spectrum analysis revealed them with the specific daughter ions. The highest sensitive ELISA-positive peak of marinobufagenin-like immunoreactivity in the media was MBT. Continuous administration of MBT in rats for 1 week significantly increased systolic blood pressure and renal excretion of marinobufagenin-like immunoreactivity compared with control rats (135+/-3.0 versus 126+/-2.0 mm Hg and 1.41+/-0.286 versus 0.34+/-0.064 ng/day, respectively). These data suggest that MBT, arginine-suberoyl ester of marinobufagenin, can be a novel digitalis-like factor with hypertensive action and is secreted from the adrenocortical cells.


Assuntos
Córtex Suprarrenal/química , Cardanolídeos/isolamento & purificação , Cardenolídeos/isolamento & purificação , Hipertensão/induzido quimicamente , Saponinas/isolamento & purificação , Córtex Suprarrenal/citologia , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Pressão Sanguínea/efeitos dos fármacos , Bufanolídeos/imunologia , Bufanolídeos/urina , Cardanolídeos/administração & dosagem , Cardanolídeos/farmacologia , Cardenolídeos/administração & dosagem , Cardenolídeos/farmacologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Esquema de Medicação , Ensaio de Imunoadsorção Enzimática , Injeções Intraperitoneais , Masculino , Espectrometria de Massas , Ratos , Ratos Wistar , Saponinas/administração & dosagem , Saponinas/farmacologia
5.
Eur J Pharmacol ; 207(1): 61-5, 1991 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-1655495

RESUMO

The onset of inhibition of Na+,K(+)-ATPase from guinea-pig myocardium was quantified with pseudo-first-order rate constants in a series of 14 cardioactive steroids. From these data the association and dissociation rate constants of the steroid-receptor complex were calculated. It was then found that the association of the steroids with receptors but not the dissociation of the steroid-receptor complex determined the largely different inhibitory potencies. Consistent with this finding, at equieffective steroid concentrations the rates of inhibition varied only slightly. The correlation of the association rate with the hydrophobicity of the compounds suggests that hydrophobic interactions facilitate the access of the steroid to the receptor. A conformational transition of the vicinity of the receptor subsequent to the formation of the steroid-receptor complex seems to alter the hydrophobic properties of the receptor environment to make the dissociation rate independent from hydrophobicity.


Assuntos
Cardanolídeos/farmacologia , Fármacos Cardiovasculares/farmacologia , Receptores de Esteroides/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Animais , Fenômenos Químicos , Físico-Química , Cobaias , Técnicas In Vitro , Cinética , Conformação Molecular
7.
J Med Chem ; 22(5): 529-33, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-222907

RESUMO

(20R)-20,22-Dihydrodigitoxigenin (3a) and (20S)-20,22-dihydrodigitoxigenin (3b) were isolated from (20R,S)-20,22-dihydrodigitoxigenin (3) by three fractional crystallizations each from ethyl acetate. The two diastereomers have distinct NMR spectra and similar (Na+,K+)ATPase inhibitory activities (I50 = 1.1-1.4 X 10(-5) M)--about 1/100 as active as digitoxigenin (1). Their activity compared with other cardenolide analogues suggests a passive geometric role for the 20(22) double bond in eliciting (Na+,K+)ATPase inhibition, keeping the lactone carbonyl in the proper orientation. (20S)-3 beta,14 beta-Dihydroxy-22-methylene-5 beta,14 beta-cardanolide (7a) was then synthesized from 3a, and (20R)-3 beta,14 beta-dihydroxy-22-methylene-5 beta,14 beta-cardanolide (7b) from 3b. They were found to be equivalently active in inhibiting (Na+,K+)ATPase, with I50 values of 7.0 x 10(-5) M. Although it has been usually believed that the 14 beta-hydroxyl of cardenolides increases binding to the receptor, 2b (the 14-ene derivative of 7b) was more than twice as active (I50 = 3.0 X 10(-5)) than either 7a or 7b.


Assuntos
Cardanolídeos/farmacologia , Animais , Encéfalo/enzimologia , Cardanolídeos/síntese química , Cardenolídeos/farmacologia , Digitoxigenina/análogos & derivados , Digitoxigenina/síntese química , Digitoxigenina/farmacologia , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Conformação Molecular , Ratos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Estereoisomerismo , Relação Estrutura-Atividade
11.
Z Gesamte Inn Med ; 31(13): 501-3, 1976 Jul 01.
Artigo em Alemão | MEDLINE | ID: mdl-785835

RESUMO

In experiments of treatment carried out on 39 patients with cardiac insufficiency with tachyarrhythmia for the partially synthetic, new heart glycoside 3',4'-dipropionyl helveticosol the following clinico-pharmacological data of efficacy were approximately established on an average: level of full efficacy 2.7 mg, daily coefficient of disappearing 40%, coefficient of enteral absorption 30%, daily maintenance dose intravenously 1.1 mg and orally 3.7 mg.


Assuntos
Glicosídeos Digitálicos/uso terapêutico , Adulto , Cardanolídeos/uso terapêutico , Ensaios Clínicos como Assunto , Glicosídeos Digitálicos/administração & dosagem , Avaliação de Medicamentos , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia/tratamento farmacológico
12.
J Pharm Sci ; 65(6): 912-4, 1976 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-945345

RESUMO

An alcoholic extract of the seeds of Coronilla varia L. showed inhibitory activity against KB cells in culture and was fractionated through a series of partitions, column chromatography, and preparative layer chromatography to yield hyrcanoside, daphnoretin, scopoletin, and umbelliferone. Hyrcanoside was also tested in the PS mouse leukemia assay and showed borderline activity.


Assuntos
Antineoplásicos , Cardanolídeos/farmacologia , Extratos Vegetais/farmacologia , Animais , Cardanolídeos/isolamento & purificação , Leucemia Experimental/tratamento farmacológico , Extratos Vegetais/análise , Sementes
14.
J Pharm Sci ; 65(5): 765-8, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-132523

RESUMO

The synthesis of a 3beta-thiocyanatocardenolide is described. The compound exhibited about 0.1 times the cardiotonic effect of digitoxyigenin in the isolated frog heart preparation. At a dosage of 20 mg/kg in the intact rat, it elicited ECG changes similar to those seen with a 10-mg/kg dose of digitoxigenin. Studies also revealed the new cardenolide to be a reversible inhibitor of sodium- and potassium-activated adenosine triphosphatase.


Assuntos
Cardanolídeos , Adenosina Trifosfatases/antagonistas & inibidores , Animais , Encéfalo/enzimologia , Cardanolídeos/síntese química , Cardanolídeos/farmacologia , Fenômenos Químicos , Química , Coração/efeitos dos fármacos , Técnicas In Vitro , Ouabaína/metabolismo , Ratos , Fatores de Tempo
15.
J Pharmacol Exp Ther ; 197(1): 19-26, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1263129

RESUMO

ASI-222,3beta-O-(4-amino-4,6-dideoxy-beta-d-galactopyranosyl) digitoxigenin, is a semi-synthetic cardiac glycoside patterned after a natural glycoside obtained from Cambodia. Effects of ASI-222 on contractile force in the isolated rabbit atria, cardiac contractile force, cardiac rate, ventricular excitability and functional refractory period in dogs, and acute toxicity in mice have been compared to those effects of ouabain. Both electrically driven and spontaneously beating atria demonstrated more rapid onset and greater maximum increases in contractile force with ASI-222 than with ouabain in equal bath concentrations. In the dog, ASI-222 increased cardiac contractile force more rapidly and at a lower cumulative dose than ouabain. Moreover, the maximum increase in contractile force obtained with ASI-222 was greater than that obtained with ouabain. The occurrence of ventricular ectopic beats was observed at a higher cumulative dose of ASI-222 than for ouabain. Also, ASI-222 produced a decrease in ventricular excitability and an increase in functional refractory period ot the ventricle. Ouabain, in the same molar dose, produced either no change or a slight increase in these parameters. Our data indicate that ASI-222 has a greater therapeutic index than ouabain. This difference may be partially explained by effects of ASI-222 on electrical properties of the heart.


Assuntos
Aminoglicosídeos/farmacologia , Cardanolídeos/farmacologia , Glicosídeos Cardíacos/farmacologia , Digitoxigenina/farmacologia , Hemodinâmica/efeitos dos fármacos , Aminoglicosídeos/toxicidade , Animais , Glicosídeos Cardíacos/toxicidade , Digitoxigenina/análogos & derivados , Digitoxigenina/toxicidade , Átrios do Coração/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Contração Miocárdica/efeitos dos fármacos , Ouabaína/farmacologia , Coelhos , Fatores de Tempo
16.
Artigo em Inglês | MEDLINE | ID: mdl-181688

RESUMO

The binding of digitoxigenin to lecithin model membranes was investigated by application of electron spin- and nuclear magnetic resonance methods. A digitoxigenin spin-label derivative was found to bind specifically to the pseudohexagonal rigid lattice of lecithin membranes. The binding is accomplished by some of the structural features which are required for the biological activity of cardiac glycosides. Digitoxigenin has a procooperative effect on dipalmitoyl-lecithin membranes. The induction of lipid phase separation is discussed as a hypothetic molecular mechanism of action of cardiac glycosides on biological membranes.


Assuntos
Cardanolídeos/metabolismo , Digitoxigenina/metabolismo , Membranas Artificiais , Fosfatidilcolinas/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Animais , Sítios de Ligação , Digitoxigenina/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Cobaias , Modelos Estruturais , Contração Miocárdica/efeitos dos fármacos , Marcadores de Spin , Temperatura
17.
J Chromatogr ; 117(1): 81-6, 1976 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-175078

RESUMO

Several multi-component liquid-systems have been investigated on silica gel SI-60 supports of particle size 10 mum. By using two solvent systems, it was possible to separate 14 digitalis glycosides, ranging from genins of relatively low polarity to the highly polar deacetyl-lanatosides. Solvents with good ultraviolet transparency at 220 nm (lambdamax. for the butenolide ring) were chosen in order to improve the sensitivity of detection. The technique should also permit the determination of by-products and degradation products of these drug substances. Detection limits are as low as 15 ng for a 5 mul injection, and separation times vary between 4 and 20 min. The reproducibility of the retention times and the baseline separations attainable make the systems suitable for quantitative work.


Assuntos
Cardanolídeos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Glicosídeos Digitálicos/isolamento & purificação , Formas de Dosagem , Géis , Métodos , Tamanho da Partícula , Dióxido de Silício , Solventes , Espectrofotometria Ultravioleta , Fatores de Tempo
20.
J Med Chem ; 18(12): 1258-61, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1195280

RESUMO

In order to determine the influence of a 6alpha-methyl group activity, the 6alpha-methyl derivative of digitoxigenin 3-acetate 14 was prepared and pharmacologically tested in comparison with digitoxigenen 3-acetate. The synthesis of 6alpha-methyldigitoxigenin 3-acetate (14) was performed starting from 21-hydroxy-4-pregnene-3,20-dione (1). According to the cardiac activity determined on guinea-pig isolated heart and by slow infusion in the cat, the 6alpha-methyldigitoxigenin 3-acetate (14) is not more active than digitoxigenin 3-acetate.


Assuntos
Cardanolídeos/síntese química , Digitoxigenina/síntese química , Animais , Gatos , Digitoxigenina/análogos & derivados , Digitoxigenina/farmacologia , Cobaias , Técnicas In Vitro , Conformação Molecular , Contração Miocárdica/efeitos dos fármacos , Estimulação Química
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