487-44-5Relevant articles and documents
Chemical structures of constituents from the leaves of Polyscias balfouriana
Sugimoto, Sachiko,Yamano, Yoshi,Khalil, Hany Ezzat,Otsuka, Hideaki,Kamel, Mohamed Salah,Matsunami, Katsuyoshi
, p. 558 - 563 (2017)
A new pyrrolidine derivative, (5S)-hydroxyethyl 2-oxopyrrolidine-5-carboxylate (1), a new flavonol glycoside, tamaraxetin 3,7-di-O-α-l-rhamnopyranoside (2), and a new triterpene saponin, polyscioside A methyl ester (3), along with six known compounds (4–9) were isolated from the leaves of Polyscias balfouriana. Their chemical structures were elucidated on the basis of extensive spectroscopic analysis.
Current perspectives on microwave-enhanced reactions of monosaccharides promoted by heterogeneous catalysts
Richel, Aurore,Laurent, Pascal,Wathelet, Bernard,Wathelet, Jean-Paul,Paquot, Michel
scheme or table, p. 141 - 147 (2012/02/04)
Involvement of heterogeneous catalysts as promoters of carbohydrate conversions, in synergy with microwaves as the heating source, is reported. This paper deals with the application of ion-exchange resins, zeolites, clays and metal oxides as convenient mediators for key transformations of carbohydrates. A special emphasis is placed on the use of (doped) mineral supports, in solventless conditions, as clean promoters in combination with microwave dielectric heating.
Degradation kinetics of glucuronic acid in subcritical water
Wang, Rongchun,Neoh, Tze Loon,Kobayashi, Takashi,Miyake, Yasuhito,Hosoda, Asao,Taniguchi, Hisaji,Adachi, Shuji
experimental part, p. 601 - 605 (2011/04/23)
The degradation kinetics of glucuronic acid (GlcA) under subcritical conditions from 160 to 200 °C was studied in a continuous tubular reactor. The formation of glucuronolactone (GlcL) during the treatment of GlcA in subcritical water was substantiated by ESITOF-MS and 1H NMR. The degradation of GlcA consisted of the reversible conversion of GlcA to GlcL and the irreversible degradation of the two compounds. The changes in the concentrations of GlcA and GlcL with residence time could be described by first-order kinetics. Higher temperatures accelerated the degradation of GlcA, and thus resulted in rises in the pH value. The degradation reaction of GlcL under the same conditions was also investigated. The activation energy of the reverse hydrolysis of GlcA to GlcL and that of the hydrolysis of GlcL to GlcA were determined to be 88.5 and 63.2 kJ/mol respectively. The enthalpy change in the reversible conversion between GlcA and GlcL was 25.4 kJ/mol.
