Showing papers on "Isovitexin published in 1995"
TL;DR: In this article, 2-hydroxy-4-6-dimethoxyacetophenone (4) was glycosylated with O-(2,3,4,6-tetra-Obenzyl-α-D-glucopyranosyl) trichloroacetimidate and trimethylsilyl triflate as promoter to yield directly the C-glycoside 6.
Abstract: 2-Hydroxy-4,6-dimethoxyacetophenone (4) was glycosylated with O-(2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl) trichloroacetimidate (5) and trimethylsilyl triflate as promoter to yield directly the C-glycoside 6. Construction of the flavone system by application of a Baker-Venkataraman-type rearrangement followed by deprotection yielded isoembigenin (2). Glycosylation of 4,6-bis(tert-butyldimethylsilyloxy)-2-hydroxyacetophenone (17) with the trichloroacetimidate 5 afforded the O-glycoside intermediate 18 which was converted via Fries rearrangement into the C-glycoside 21. Applying again the Baker-Venkataraman rearrangement and cyclization gave isovitexin and vitexin derivatives 25 and 26, which were completely deprotected to yield isovitexin (1b) and vitexin (1a), respectively.
43 citations
TL;DR: Lutonarin was isolated from Bryonia alba and B. dioica together with saponarin caffeic ester, a new natural product, and five further C-glycosides: vitex in, isovitexin, isoorientin, sapon Karin were isolated from B. Dioica.
26 citations
TL;DR: The results lend some support for the separation of Macroptilium, Strophostyles and Dysolobium from Phaseolus, but they also indicate considerable heterogeneity in flavonoid patterns within the Phaseolinae.
17 citations
Patent•
07 Nov 1995
TL;DR: In this article, the subject antioxidant contains 2''-O-glucosyl isovitexin (hereinafter abbreviated GIV) as the active component and has an excellent antioxidation effect on a fish oil.
Abstract: PURPOSE:To obtain the subject antioxidant containing a specified glucosyl isovitexin extracted from a barley-related plant, etc., as the active component and having an excellent antioxidation effect on a fish oil containing a fatty acid having a high degree of unsaturation. CONSTITUTION:This antioxidant contains 2''-O-glucosyl isovitexin (hereinafter abbreviated GIV) as the active component and has an excellent antioxidation effect on a fish oil, e.g. preferably a food containing docosahexaenoic acid, eicosapentaenoic acid and/or octadecatetraenoic acid. In addition, GIV is used recommendably, e.g. in the form of a squeezed juice of green leaves of a green plant, e.g. a barley-related plant such as barley, its dried powder, a green leaf fiber powder, a GIV-containing extract, a crudely purified material or an isolated substance in an amount within a range of 0.01 to 2wt.% based on the weight of the fish oil.
1 citations