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11.
The aerial parts of Daphne sericea yielded two new flavonoids, luteolin 7-methyl ether 5-β-d-glucoside and luteolin 7,3′-dimethyl ether 5-β-d-glucoside, as well as luteolin 7-methyl ether, isovitexin, apigenin and its 7-β-d-glucoside. 相似文献
12.
A new diol glucoside, 2-β-d-glucopyranosyloxy-2-methylpropanol, the first reported naturally occurring monoglucoside of an aliphatic dihydric alcohol, was isolated from pods of Acacia sieberana var. woodii. Structure elucidation was based on 1 H and 13C NMR spectroscopy, and enzymatic analyses. The compound was hydrolysed very slowly by almond β-glucosidase, but cleaved by a β-glucuronidase enzyme complex from Helix pomatia. 相似文献
13.
Treatment of Sendai virus with , followed by freezing and thawing resulted in a loss of hemolytic and cell fusion activities as well as infectivity without affecting hemagglutinating and neuraminidase activities. The anti-hemolytic activity of this compound was reversed by the addition of phosphatidyl choline to the virus samples. was successfully used for photoaffinity labeling of a specific virion site, and we confirmed the affected site of the glucoside to be the lipid components in the viral envelopes. 相似文献
14.
Four monolignol glucosides have been isolated and identified from the needles of Pinus contorta. Chavicol 4-O-α-L-arabinofuranosyl-(1 → 相似文献
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16.
From dried leaves of Panax pseudo-ginseng subsp. himalaicus collected in Eastern Himalaya, new dammarane saponins, named pseudo-ginsenosides-F11 and -F8 were isolated along with the known Ginseng-root saponins, ginsenosides-Rb3, Rd and -Re. Pseudo-ginsenoside-F8 was proved to be a mono-acetyl-ginsenoside-Rb3 and the location of its acetyl group was established mainly by 13C NMR spectroscopy. Pseudo-ginsenoside-F11, was identified as the 6-O-α-rhamnopyransyl(1 → 2)-β-glucopyranoside of 3β,6α,12β,25-tetrahydoxy-(20S,24R)-epoxy-dammarane. The C-24 configuration of ocotillone and its related triterpenes was confirmed to be 24R excluding the recent comment by Lavie et al. 相似文献
17.
A new triterpenoid glycoside containing an amino sugar moiety has been isolated from Pithecellobium cubense and P. arboreum and identified as O(3)- (2-acetylamino-2-deoxy-β-d-glucopyranosyl)oleanolic acid. β-d-Glucopyranosyl-α-spinasterol was also obtained from P. cubense. 相似文献
18.
Investigation of the North American species Psilostrophe villosa afforded, in addition to known compounds, five new sesquiterpene lactones, which all turn out to be modified pseudoguaianolides, most of them closely related to hymenolide. However, one of the lactones is a new type of nor-pseudoguaianolide. Furthermore a new monoacetylated borneol-β-D-glucoside is present. The chemotaxonomic situation is discussed briefly. 相似文献
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20.
Acacipetalin, previously known only from the African legumes Acacia sieberiana var. woodii and Acacia hebeclada, has been isolated from an American species of the genus, Acacia constricta. 相似文献