Results 201 to 210 of about 4,729 (242)
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Synthesis of cardenolide glycosides and putative biosynthetic precursors of cardenolide glycosides
Steroids, 1998A rapid and efficient procedure for glycosylation of steroids was established using a modified Koenigs-Knorr procedure. Peracetylated beta-glycosides were synthesized by reaction of cardenolides, various pregnanes and 23-nor-5,20(22)E-choldienic acid at room temperature with the peracetylated 1-bromo derivatives of D-glucose, D-galactose, D-fucose and ...
M, Luta, A, Hensel, W, Kreis
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Cytotoxic cardenolides from Calotropis gigantea
Phytochemistry, 2021Sixteen cardiac glycosides, including five previously undescribed compounds, were extracted and purified from whole plants of Calotropis gigantea (L.). Spectroscopic data and electronic circular dichroism (ECD) analyses were used to determine their structures.
Yi-Lin, He +4 more
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Chemischer Informationsdienst, 1984
AbstractBehandeln der Cardenolide (I) mit NaH in DMF, anschließen de Zugabe der Alkylhalogenide (II) binnen fünf Minuten und Ansäuern der Ansätze liefern die Monoalkylderivate (III) als Hauptprodukte, daneben die Dialkylderivate (IV).
B. STRECKENBACH +4 more
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AbstractBehandeln der Cardenolide (I) mit NaH in DMF, anschließen de Zugabe der Alkylhalogenide (II) binnen fünf Minuten und Ansäuern der Ansätze liefern die Monoalkylderivate (III) als Hauptprodukte, daneben die Dialkylderivate (IV).
B. STRECKENBACH +4 more
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Two cardenolides fromCalotropis procera
Magnetic Resonance in Chemistry, 1999Two cardiotonic glycosides were isolated from Calotropois procera; one of them (1) is a new natural product. Their structures were elucidated by extensive application of oneand two-dimensional 1H and 13C NMR spectroscopy. Copyright 1999 John Wiley & Sons, Ltd.
Atef G. Hanna +5 more
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ChemInform Abstract: CARDENOLIDES. I. RING D CLEAVAGE OF CARDENOLIDES
Chemischer Informationsdienst, 1982AbstractDie Einwirkung von Ozon auf die Cardadienolide (I) und nachfolgende reduktive Aufarbeitung führen überraschenderweise nicht zum Abbau des Butenolidringes, sondern nahezu ausschließlich zur D‐Ringspaltung unter Bildung der 14,1 S‐Seeocardenolide (IIa) und (IIb) bzw. (Ile).
E. COHNEN, K. WEDEMEIER, V. SINNWELL
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Chemischer Informationsdienst, 1981
AbstractDas Ausgangsprodukt für die Synthesen der Cardenolid‐Analogen (VII) bzw. (XI) ist das aus dem Iodketon (I) erhaltene (II).
F. THEIL, C. LINDIG, K. REPKE
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AbstractDas Ausgangsprodukt für die Synthesen der Cardenolid‐Analogen (VII) bzw. (XI) ist das aus dem Iodketon (I) erhaltene (II).
F. THEIL, C. LINDIG, K. REPKE
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Chemistry of Natural Compounds, 2005
3-Keto-derivatives of the cardenolides digitoxigenin and cardiogenin were prepared with subsequent conversion to new ketoimines (1–19, 24–44), the oxime (23), and for the first time to pure cardiogenin (14,16-dianhydrogitoxigenin, 20), its acetate (21), and cardiogenone (22). Their physicochemical properties were described.
I. F. Makarevich +2 more
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3-Keto-derivatives of the cardenolides digitoxigenin and cardiogenin were prepared with subsequent conversion to new ketoimines (1–19, 24–44), the oxime (23), and for the first time to pure cardiogenin (14,16-dianhydrogitoxigenin, 20), its acetate (21), and cardiogenone (22). Their physicochemical properties were described.
I. F. Makarevich +2 more
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Journal of Fluorine Chemistry, 1985
Abstract For estimation of the influence of fluorination at C21 of the lactone ring of cardenolides on their cardiac activity we have synthesized 21α- and 21β-fluoro-cardenolides by treatment of 21β-bromo-cardenolides with AgF. Prior to allylic bromination of cardenolides their OH- groups are protected by CCl 3 CH 2 OCO- groups and deprotected after ...
R. Megges +5 more
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Abstract For estimation of the influence of fluorination at C21 of the lactone ring of cardenolides on their cardiac activity we have synthesized 21α- and 21β-fluoro-cardenolides by treatment of 21β-bromo-cardenolides with AgF. Prior to allylic bromination of cardenolides their OH- groups are protected by CCl 3 CH 2 OCO- groups and deprotected after ...
R. Megges +5 more
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Partialsynthesen von Cardenoliden und Cardenolid‐Analogen. VIII. Lactonring‐alkylierte Cardenolide
Journal für Praktische Chemie, 1983Partial Syntheses of Cardenolides and Cardenolide Analogues. VIII. Lactone Ring‐Alkylated CardenolidesBase‐catalyzed alkylation of digitoxigenin (1), digitoxin (2), digoxigenin (3), and gitoxigenin‐3,16‐diacetate (4) with allyl bromide, allyl chloride or n‐propyl bromide in DMF resulted in the formation of the 22‐allyl‐, 21ξ,22‐diallyl‐, 22‐propyl ...
Barbara Streckenbach +4 more
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SYNTHETIC CARDENOLIDES AND RELATED PRODUCTS
Pure and Applied Chemistry, 1970Abstract
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