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1.
Phytochemical investigation of polar extract from Juniperus oxycedrus spp. oxycedrus berries leds to the isolation of one new monoterpene glucoside (3R,6E)-3,7 dimethyl 8-hydroxy-6-octenoic acid 8-O-β-d-glucopyranoside along with seven known components, some of them were initially isolated from Juniperus communis L. berries. Their structures were established on the basis of extensive 1D and 2D NMR (1H, 13C, COSY, HMBC, HSQC, ROESY) and ESI-MS studies. The n-butanol fraction and isolated components, shikimic acid (2), compound 3, 4 and 5 were evaluated, in vitro, for their effect on cell viability against human malignant melanoma (A375), breast (MCF-7) and lung (H460) cancer cell lines. Shikimic acid exhibited selective effect on cell viability only against breast MCF-7 cell lines reaching IC50 value at dose of 30 μM and also induced the level decrease of vascular endothelial growth factor (VEGF) and five pro-inflammatory cytokines suggesting its potential anti-inflammatory effect.  相似文献   
2.
A new phenolic glucoside, acremonoside (1), along with two known compounds, F-11334 A2 and 2,2-dimethyl-2H-chromen-6-ol, were isolated from the sea fan-derived fungus Acremonium polychromum PSU-F125. The structure of 1 was elucidated by spectroscopic techniques, acid hydrolysis and X-ray crystallographic analysis. The isolated compounds were tested for antibacterial, antimalarial, antimycobacterial and cytotoxic activities.  相似文献   
3.
From three Fouquieria sp. 12 iridoid glucosides were isolated and identified. Eight of these were structurally related to galioside (monotropein methylester), while four were hydroxy substitution products of deoxyloganin. In three cases the glucoside occurred together with the corresponding 10-O-acetate.  相似文献   
4.
枇杷叶的化学成分   总被引:6,自引:0,他引:6  
枇杷叶系蔷薇科(Rosaceae)枇杷属植物枇杷[Eriobotrya japonica(Thunb.)Lindl.]的干燥叶,为常用中药,收载于历版《中华人民共和国药典》中。枇杷叶归肺、胃经,具清肺止咳、降逆止呕的作用,用于治疗肺热咳嗽、气逆喘气、胃热呕逆及烦热口渴之症状。目前,已经从枇杷叶中分离出三萜酸、黄酮类、多酚、倍半萜及其苷类等成分,对其药效的研究主要集中在三萜酸的抗炎心、降血糖和抗病毒活性等方面。  相似文献   
5.
In the course of screening for antioxidative carotenoids from bacteria, we isolated and identified a novel carotenoid, OH-chlorobactene glucoside hexadecanoate (4), and rare carotenoids, OH-chlorobactene glucoside (1), OH-γ-carotene glucoside (2) and OH-4-keto-γ-carotene glucoside hexadecanoate (3) from Rhodococcus sp. CIP. The singlet oxygen (1O2) quenching model of these carotenoids showed potent antioxidative activities IC50 14.6 μM for OH-chlorobactene glucoside hexadecanoate (4), 6.5 μM for OH-chlorobactene glucoside (1), 9.9 μM for OH-γ-carotene glucoside (2) and 7.3 μM for OH-4-keto-γ-carotene glucoside hexadecanoate (3).  相似文献   
6.
Zygaena filipendulae accumulates the cyanogenic glucosides linamarin and lotaustralin by larval sequestration from the food plant or de novo biosynthesis. We have previously demonstrated that the Z. filipendulae male transfers linamarin and lotaustralin to the female in the course of mating. In this study we report the additional transfer of 5-hydroxytryptophan glucoside (5-(β-d-glucopyranosyloxy)-l-Tryptophan) from the Z. filipendulae male internal genitalia to the female spermatophore around 5 h into the mating process. 5-Hydroxytryptophan glucoside is present in the virgin male internal genitalia, and production continues during the early phase of mating. Following initiation of 5-hydroxytryptophan glucoside transfer to the female, the amount in male internal genitalia is drastically reduced until after mating where it is slowly replenished. For unambiguous structural identification, 5-hydroxytryptophan glucoside was chemically synthesized and used as an authentic standard. The biological function of 5-hydroxytryptophan glucoside remains to be established, although we have indications that it may be involved in inducing the female to stay in copula and delay egg-laying to prevent re-mating of the female. To our knowledge 5-hydroxytryptophan glucoside has not previously been reported present in animal tissues.  相似文献   
7.
Investigation of yellow flower extract of Tagetes patula L. led to the identification of an aggregate of five phytoceramides. Among them, (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,8E)‐1,3,4‐trihydroxyicos‐8‐en‐2‐yl]icosanamide, (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,8E)‐1,3,4‐trihydroxyicos‐8‐en‐2‐yl]heneicosanamide, (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,8E)‐1,3,4‐trihydroxyicos‐8‐en‐2‐yl]docosanamide, and (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,8E)‐1,3,4‐trihydroxyicos‐8‐en‐2‐yl]tricosanamide were identified as new compounds and termed as tagetceramides, whereas (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,8E)‐1,3,4‐trihydroxyicos‐8‐en‐2‐yl]tetracosanamide was a known ceramide. A steroid (β‐sitosterol glucoside) was also isolated from the subsequent fraction. The structures of these compounds were determined on the basis of spectroscopic analyses, as well as chemical method. Several other compounds were also identified by GC/MS analysis. The fractions and some commercial products, a ceramide HFA, β‐sitosterol, and stigmasterol were evaluated against an economically important cyst nematode, Heterodera zeae. Ceramide HFA showed 100 % mortality, whereas, β‐sitosterol and stigmasterol were 40–50 % active, at 1 % concentration after 24 h of exposure time, while β‐sitosterol glucoside revealed no activity against the nematode.  相似文献   
8.
The isolation and structure determination of a glycosidic germacradienolide from Eupatorium altissimum are reported. Eupatorin and 5-hydroxy-3′,4′,6,7-tetramethoxyflavone were also found.  相似文献   
9.
A new diterpene glucoside has been isolated from Leucothoe grayana. Its structure was elucidated by X-ray diffraction analysis of a dehydrated product of the aglycone and conversion of the same to leucothol A.  相似文献   
10.
One new (1, SZMT01) and one known (2) anti-aging substances were isolated from Shenzhou honey peach fruit. Their structures were elucidated by spectroscopic methods and chemical derivatization, and the result reveals that these two compounds are sesquiterpene glucosides. SZMT01 possesses a new glycosylation with an ester linkage at one terminal in an acyclic sesquiterpenoid which is the end of a double bond at another terminal. Both compounds extend the replicative lifespan of K6001 yeast strain at doses of 7.5 and 25 μM. Then, to understand the action mechanism involved, we performed an anti-oxidative experiment on SZMT01. The result revealed that treatment with SZMT01 increased the survival rate of yeast under oxidative stress. Moreover, the lifespans of sod1 and sod2 mutant yeast strains with a K6001 background were not affected by SZMT01. These results demonstrate that anti-oxidative stress performs important roles in anti-aging effects of SZMT01.  相似文献   
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