4321-20-4Relevant articles and documents
Thermal Degradation of Glycosides, VI - Hydrothermolysis of Cardenolide and Flavonoid Glycosides
Kim, Youn Chul,Higuchi, Ryuichi,Komori, Tetsuya
, p. 575 - 580 (2007/10/02)
The hydrothermolysis of cardenolide and flavonoid glycosides is described.On heating with water or water/dioxane, cardenolide (1, 5, 11) and flavonoid glycosides (16, 20, 23, 27) are converted into their genuine aglycones and partially hydrolyzed products, together with saccharide components.Meanwhile, the glycosidic linkage of 2-deoxy sugar moieties in cardenolide glycosides is more readily cleaved than that of the common sugar moieties by means of hydrothermolysis.Therefore, hydrothermolysis of the uzarigenin triglycoside (13), bearing a 2-deoxy sugar moiety whichis directly attached to the aglycone, leads to selective cleavage of the sugar-aglycone linkage.The hydrothermolyzed products have been isolated by chromatography and their structures elucidated by spectroscopic methods. Key Words: Thermolysis / Degradation, thermal / Carbohydrates / Glycosides / Cardenolides / Steroids / Flavonoids
Thermal Degradation of Glycosides, II. - Thermal Effect on Acetates of Typical Triterpenoid and Steroid Glycosides
Higuchi, Ryuichi,Noguchi, Yuko,Kitamura, Yoichi,Kim, Youn Chul,Komori, Tetsuya
, p. 775 - 780 (2007/10/02)
The thermal effect on acetates of triterpenoid and steroid glycosides was examined.Contrary to the case of free glycosides, on heating the acetates of typical triterpenoid and steroid glycosides (including cardiac glycosides) on a melting point apparatus the cleavage reactions of sugar-aglycone and sugar-sugar linkage did not take place, and no aglycones or prosapogenins were obtained.However, two interesting and useful reactions did occur in the course of thermolysis of cardiac glycoside acetates.By taking into account the thermal effect on the glycoside acetates, and their FD mass spectra, an important suggestion on the mechanism of FD mass fragmentation of the glycosidic linkage was obtained.
