Results 171 to 180 of about 2,581 (218)

Chemie der Ginkgolide, IV. Herstellung von Ginkgolid B aus Ginkgolid C

Liebigs Annalen der Chemie, 1991
Chemistry of Ginkgolides, IV1). – Synthesis of Ginkgolide B from Ginkgolide CThe reaction of ginkgolide C (3) with tert‐butylchlorodiphenylsilane results exclusively in the formation of the 1‐O‐tert‐butyldiphenylsilyl ether 5, which when treated with O‐phenylchlorothioformate leads to the 7‐phenyloxythiocarbonyl derivative 6.
Klaus Weinges, Hartmut Schick
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Regioselective thionocarbonation of ginkgolides: facile preparation of ginkgolide J

Tetrahedron Letters, 2005
Ginkgolide J, a minor constituent of terpene trilactone mixture of Ginkgo biloba leaves extract, can be readily prepared from an abundant ginkgolide C in two steps: thionocarbonation and subsequent deoxygenation. Regioselectivity of the first thionocarbonation step can be controlled by a proper choice of the base and solvent combination.
Sergei V. Dzyuba, Sergei Bolshakov, Koji Nakanishi   +2 more
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ChemInform Abstract: Chemistry of Ginkgolides. Part 4. Synthesis of Ginkgolide B from Ginkgolide C.

ChemInform, 1991
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
K. WEINGES, H. SCHICK
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Ginkgolide

Chemie in unserer Zeit, 2015
AbstractDie Ginkgolide sind neben dem Bilobalid und einer Reihe an Flavonoiden die wichtigsten Wirkstoffe des Ginkgo‐Baums (Ginkgo biloba). Sie entstammen dem Terpenstoffwechsel und werden durch Zyklisierung von Geranylgeranyldiphosphat, oxidativer Funktionalisierung und Gerüstumlagerungen aufgebaut.
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Three ginkgolide hydrates fromGinkgo bilobaL.: ginkgolide A monohydrate, ginkgolide C sesquihydrate and ginkgolide J dihydrate, all determined at 120 K

Acta Crystallographica Section C Crystal Structure Communications, 2002
A low-temperature structure of ginkgolide A monohydrate, (1R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11aS)-3-(1,1-dimethylethyl)-hexahydro-4,7b-dihydroxy-8-methyl-9H-1,7a-epoxymethano-1H,6aH-cyclopenta[c]furo[2,3-b]furo[3',2':3,4]cyclopenta[1,2-d]furan-5,9,12(4H)-trione monohydrate, C(20)H(24)O(9) x H(2)O, obtained from Mo K alpha data, is a factor of three more
Jianping, Zhao, Ilias, Muhammad, D Chuck, Dunbar, Ikhlas A, Khan, Nikolaus H, Fischer, Frank R, Fronczek   +5 more
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Chemistry of the Ginkgolides. Part 10: Access to 14C-Labelled Ginkgolide A

Tetrahedron, 2000
Abstract In four reaction steps, ginkgolide A ( 1 ) was synthesized from the enol-acetate 3 , which is available in six steps from 1 . The key step was the reaction of the α-epoxy-acetate 4 with the lithium enolate of methyl propionate to give the compounds 5 and 6 . 14 C-Labelled ginkgolide A, which is of interest for pharmacological studies,
Klaus Weinges, Hartmut Schick, Hermann Irngartinger, Thomas Oeser   +3 more
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[Effect of compatibility of ginkgolide A, ginkgolide B and ginkgolide K].

Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica, 2019
To investigate the best active compatibility of ginkgolide A, B and K (GA，GB，GK). The effects of GA, GB, GK alone, combinations of each two of them, and combinations of these three components on platelet-activating factor (PAF)-induced platelet aggregation activity and rat cerebral ischemia reperfusion model (tMCAO) were compared in this study ...
Hong, Zhang, Yan-Ping, Luo, Ze-Yu, Cao, Xin-Zhuang, Zhang, Liang, Cao, Zhen-Zhong, Wang, Wei, Xiao   +6 more
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Pharmacokinetics and tissue distribution of ginkgolide A, ginkgolide B, and ginkgolide K after intravenous infusion of ginkgo diterpene lactones in a rat model

Journal of Pharmaceutical and Biomedical Analysis, 2016
Ginkgo diterpene lactones are compounds that are extracted from the Ginkgo biloba leaf and possess pharmacologic activities with neuroprotective effects. To address the poor bioavailability of ginkgo diterpene lactones, ginkgo diterpene lactone meglumine injection (GDLI) was formulated and is commercially available.
Shuyao, Wang, Bingchen, Ouyang, Jiye, Aa, Jianliang, Geng, Fei, Fei, Pei, Wang, Jiankun, Wang, Ying, Peng, Ting, Geng, Yanjing, Li, Wenzhe, Huang, Zhenzhong, Wang, Wei, Xiao, Guangji, Wang   +13 more
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ChemInform Abstract: Chemistry of the Ginkgolides. Part 5. Preparation of the Ginkgolide Skeleton.

ChemInform, 1993
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
K. WEINGES, M. RUEMMLER, H. SCHICK, G. SCHILLING   +3 more
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Characterizations of the hydrolyzed products of ginkgolide A and ginkgolide B by liquid chromatography coupled with mass spectrometry

Journal of Pharmaceutical and Biomedical Analysis, 2016
Ginkgolides are diterpenoid trilactones responsible for the neuromodulatory properties of Ginkgo biloba extracts. They are to be hydrolyzed in aqueous solutions as mixed carboxylate forms potentially including three monocarboxylates, three dicarboxylates and one tricarboxylate.
Ke, Lan, Xue-Jing, Li, Gang, Du, Liang, Xu   +3 more
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