排序方式: 共有51条查询结果,搜索用时 250 毫秒
41.
42.
Proanthocyanidin glycosides and related polyphenols from cacao liquor and their antioxidant effects 总被引:5,自引:0,他引:5
Hatano T Miyatake H Natsume M Osakabe N Takizawa T Ito H Yoshida T 《Phytochemistry》2002,59(7):749-758
Purification of polar fractions from cacao liquor extracts gave 17 phenolics including four new compounds. The new compounds were characterized as a C-glycosidic flavan, an O-glycoside of a dimeric and two O-glycosides of trimeric A-linked proanthocyanidins, on the basis of spectroscopic data. Isolated polyphenols showed inhibitory effects on nicotinamide adenine dinucleotide phosphate-dependent lipid peroxidation in microsomes and on the autoxidation of linoleic acid. These effects were attributed to the radical-scavenging activity in the peroxidation chain reactions, based on the findings that the cacao polyphenols effectively scavenged the 1,1-diphenyl-2-picrylhydrazyl radical. 相似文献
43.
The cyclic peptide alkaloid, chamaedrine, was isolated from the roots of Melochia chamaedris (Sterculiaceae), along with four known cyclic peptide alkaloids (adouetine X, frangulaline, scutianine B and scutianine C), and waltherione A, parasorbic acid, propacine, and (-)-epicatequine. Their structures were elucidated on the basis of spectroscopic analysis, especially by 2D NMR ((1)H-(1)H-COSY, NOESY, HMQC, HMBC). 相似文献
44.
Three coumarins and three known mansonones were isolated from the heartwood of Mansonia gagei Drumm. The structures of the three coumarins were elucidated as 3,8-dimethyl-5-isopropyl-6-methoxycoumarin (mansonrin A) 3,8-dimethyl-5-isopropyl-6-hydroxycoumarin (mansorin B) and 2,3-dihydro-3,6,9-trimethyl naphtho[1,8-bc]pyran-7-oxa-8-one (mansorin C) by analyses of physical properties and spectroscopic data. The cytotoxicity of the isolated compounds against brine shrimp Artemia salina Linn. was also evaluated. 相似文献
45.
Tang Ya 《植物分类学报:英文版》1993,31(4):297-308
The systematic position of Paradombeya Stapf has been debated until now. The
studies on gross morphology, anatomy, palynology and cytology were undertaken to confirm the systematic position and affinities of this genus. The combination of features, e. g.,
umbel-like cyme, 2-celled anther, presence of staminodes, staminal tube, 15 stamens,
bifid cotyledons, wood anatomy, chromosome number of 2n=20, triporate, spiny and
spheroidal pollen grains, suggests that the genus be better placed in the tribe Dombeyeaeof the Sterculiaceae. 相似文献
46.
Ron Scogin 《Biochemical Systematics and Ecology》1979,7(1):35-36
No uncommon anthocyanins were detected among 13 taxa (sig genera) of the Sterculiaceae. Floral pigments appear to be of little systematic utility in this family. 相似文献
47.
48.
Scutianine B and two new cyclopeptide alkaloids, melonovines A and B have been isolated from Melochia tomentosa. 相似文献
49.
50.