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1.
J Org Chem ; 82(23): 12377-12385, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29090580

RESUMO

A new cyclopropane-containing sesquiterpenoid, phellilane L (1), was isolated from the medicinal mushroom Phellinus linteus ("Meshimakobu" in Japanese), a member of the Hymenochaetaceae family and a well-known fungus that is widely used in East Asia. The planar structure of 1 was determined on the basis of spectroscopic analysis. The authors achieved the first total synthesis of 1. Our protecting group-free synthesis features a highly stereoselective one-pot synthesis involving an intermolecular alkylation/cyclization/lactonization strategy for construction of the key cyclopropane-γ-lactone intermediate. Additionally, our synthesis determined the absolute configuration of phellilane L (1).


Assuntos
Agaricales/química , Basidiomycota/química , Sesquiterpenos/química , Química Farmacêutica , Estrutura Molecular
4.
Planta ; 218(3): 456-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14523650

RESUMO

A cDNA encoding UDP-glucose: formononetin 7- O-glucosyltransferase, designated UGT73F1, was cloned from yeast extract-treated Glycyrrhiza echinata L. cell-suspension cultures using probes from Scutellaria baicalensis UDP-glucose: flavonoid 7- O-glucosyltransferase. The open reading frame of the UGT73F1 cDNA encodes a 441-amino-acid protein with a predicted molecular mass of 48.7 kDa. The deduced amino acid sequence showed that the protein is related to the stress-inducible glucosyltransferases. UGT73F1 mRNA was not detected in untreated G. echinata cultures but was transiently induced by treatment with yeast extract. Recombinant UGT73F1 was expressed as a histidine-tag fusion protein in Escherichia coli and purified to near homogeneity by nickel chelate chromatography. The purified recombinant enzyme was selective for isoflavonoid, formononetin and daidzein as substrates, while flavonoids and various tested non-flavonoid compounds were poor substrates.


Assuntos
DNA de Plantas/genética , Glucosiltransferases/genética , Glycyrrhiza/genética , Isoflavonas/genética , Células Cultivadas , Clonagem Molecular , DNA Complementar/genética , Glucosiltransferases/metabolismo , Glycyrrhiza/classificação , Glycyrrhiza/enzimologia , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Especificidade por Substrato
5.
Phytochemistry ; 61(5): 589-95, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12409027

RESUMO

Two blazeispirane derivatives including blazeispirols G and I were isolated from the cultured mycelia of the fungus Agaricus blazei Murill and were established to be (20S, 22S, 23R, 24S)-14 beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-triene-11 alpha,23-diol and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-23,28-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. Furthermore, four blazeispirol derivatives blazeispirols, U, V, V(1) and Z(1) were isolated form the same source described above. Their structures were determined to be (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxyergosta-4,6,8,11-tetraen-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 alpha,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 beta,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxy-4,5-seco-ergosta-6,8-diene-3,5-dione by extensive 1 D and 2D NMR spectral data.


Assuntos
Agaricus/química , Micélio/química , Esteroides/química , Esteroides/isolamento & purificação , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Estrutura Molecular
6.
Phytochemistry ; 60(4): 351-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12031424

RESUMO

Three flavonoids named licoagrosides D, E and F together with four known flavonoids, medicarpin 3-O-glucoside, calycosin 7-O-glucoside, formononetin 7-O-(6"-malonylglucoside) and 2'-hydroxyformononetin 7-O-glucoside were isolated from Glycyrrhiza pallidiflora hairy root cultures. Their structures were determined on the basis of spectroscopic evidence. Licoagrosides E and F are the first examples of a 6a-hydroxypterocarpan glycoside and an alpha-O-glycosidic alpha-hydroxydihydrochalcone, respectively.


Assuntos
Flavonoides/química , Flavonoides/isolamento & purificação , Glycyrrhiza/química , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Glicosídeos/química , Ressonância Magnética Nuclear Biomolecular/métodos , Extratos Vegetais/química , Plantas Medicinais/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta , Análise Espectral
7.
Phytochemistry ; 59(5): 571-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11853754

RESUMO

Four new des-A-ergostane derivatives including blazeispirols B, C, E and F were isolated from the cultured mycelia of fungus Agaricus blazei Murill and were established to be (20S, 22R, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraen-23-ol; (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-trien-23-ol; (20S, 22S, 23R, 24S)-14beta, 22: 22, 25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-19,23-diol and (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-des-A-ergosta-5,7,9-triene-5,23-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A.


Assuntos
Agaricus/química , Ergosterol/análogos & derivados , Ergosterol/isolamento & purificação , Ergosterol/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho
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