Intramolecular stabilization of acylated betacyanins
摘要:
Racemization and stability of the betacyanins, betanin (betanidin 5-O-glucoside) and amaranthin (betanidin 5-O-glucuronosylglucoside), under acidic conditions were compared with those of the corresponding feruloyl derivatives, lampranthin II and celosianin II. Both acylbetacyanins showed a reduced racemization velocity and celosianin II in addition an enhanced stability, possibly caused by intramolecular association between the betanidin and the feruloyl moieties. (C) 1998 Elsevier Science Ltd. All rights reserved.
Intramolecular stabilization of acylated betacyanins
作者:Willibald Schliemann、Dieter Strack
DOI:10.1016/s0031-9422(98)00047-8
日期:1998.9
Racemization and stability of the betacyanins, betanin (betanidin 5-O-glucoside) and amaranthin (betanidin 5-O-glucuronosylglucoside), under acidic conditions were compared with those of the corresponding feruloyl derivatives, lampranthin II and celosianin II. Both acylbetacyanins showed a reduced racemization velocity and celosianin II in addition an enhanced stability, possibly caused by intramolecular association between the betanidin and the feruloyl moieties. (C) 1998 Elsevier Science Ltd. All rights reserved.
Cyclodopa glucoside ( = (2S)-5-(?-D-glocopyranosyloxy)-6-hydroxyindoline-2-carboxylic acid) and its occurrence in red beet (beta vulgaris var.rubra L.)
Cyclodopaglucoside ( = (2S)-5-(β-D-glucopyranosyloxy)-6-hydroxyindoline-2-carboxylicacid; 1a) is prepared from betainin (2a) via a base exchange reaction. Its purification and physical properties are described. The compound is N-formylated in dilute HCOOH solution. Cyclodopaglucoside is contained in considerable amount in redbeet juice varying from 0.07 to 1.9 mmol/kg or from 12 to 46% relative to