共查询到19条相似文献,搜索用时 171 毫秒
1.
从狗枣猕猴桃叶中分离出4个新的黄酮类化合物, 经1D NMR, 2D NMR及ESI-MS等波谱分析鉴定了其结构, 分别是4'-甲氧基-槲皮素-7-O-(4"-O-乙酰基-鼠李糖基)-3-O-β-D-吡喃葡萄糖苷(1), 山柰甲黄素-7-O-(3"-O-乙酰基-鼠李糖基)-3-O-芸香糖苷(2), 山柰酚-7-O-(4"-O-乙酰基-鼠李糖基)-3-O-芸香糖苷(3)和4'-甲氧基-槲皮素-7-O-(4"-O-乙酰基-鼠李糖基)-3-O-芸香糖苷(4). 相似文献
2.
全二维液相色谱串联质谱用于银杏叶提取物成分分析的研究 总被引:8,自引:0,他引:8
建立了全二维液相色谱串联质谱分离分析模式,将质脂体色谱柱和ODS反相色谱柱作为二维分析色谱柱,二者通过一个连有两个0.5 mL定量环的八通阀耦联。质脂体色谱柱上的馏分在反相色谱柱上分离后,直接进入紫外-检测器,然后经分流器分流后进入大气压电离质谱。将该体系用于银杏叶提取物的组成研究,共检测到至少41个组分,结合紫外-可见光谱和质谱信息,其中13个组分初步鉴定为银杏内酯B、银杏内酯C、白果内酯、槲皮素芸香糖苷、槲皮素、槲皮素-3-O-β-D-葡萄糖基(1-2)-α-L-鼠李糖苷、槲皮素-3-O-β-D-葡萄糖苷、异鼠李素、山柰酚-3-O-β-D-芸香糖基(1-2)-α-L-鼠李糖苷、异鼠李素-3-O-β-D-芸香糖苷、山柰酚-3-O-β-D-葡萄糖苷、山柰酚和山柰酚-3-O-β-D-芸香糖苷。 相似文献
3.
云南大花红景天化学成分研究 总被引:14,自引:0,他引:14
从云南丽江产民间药物大花红景天(Rhodiola crenulata)根的乙醇提取物中分离得到10个化合物, 经化学方法和光谱数据分析, 10个化合物结构鉴定为: 山奈酚(1), 山奈酚7-O-α-L-鼠李糖苷(2), 大花红景天苷(3), 草质素7-O-α-L-鼠李糖苷(4), 草质素7-O-(3"-O-β-D-葡萄糖基)-α-L-鼠李糖苷(5), 大花红景天素(6),鞣花酸(7), 红景天苷(8), 没食子酸(9), 没食子酸乙酯(10)。其中化合物1, 2,3, 6, 7是首次从大花红景天中得到, 化合物3-为一新的山奈酚苷, 用13^C NMR,1^H-1^H COSY, 13^C-1^H COSY谱确证6为一种结构罕见的黄酮醇与苯丙素结合而成的化合物。 相似文献
4.
高速逆流色谱法分离制备乌药叶中的黄酮类成分 总被引:3,自引:0,他引:3
应用高速逆流色谱法分离制备了乌药叶中的黄酮类成分。以正己烷-乙酸乙酯-正丁醇-冰醋酸-水(体积比为2∶4∶2∶1.5∶6)为两相溶剂系统,在主机转速800 r/min、流速2.0 mL/min、检测波长280 nm条件下进行分离制备。所得流分经高效液相色谱法检测,并经电喷雾电离质谱、核磁共振氢谱、碳谱鉴定化合物的结构。结果表明,从乌药叶总黄酮粗提物中分离得到了5个化合物,分别为槲皮素-3-O-β-D-葡萄糖苷(1)、槲皮素-5-O-β-D-葡萄糖苷(2)、槲皮素-3-O-β-D-呋喃阿拉伯糖苷(3)、槲皮素-3-O-吡喃鼠李糖苷(4)、山奈酚-7-O-α-L-吡喃鼠李糖苷(5),其中化合物1,2,3和5 为首次从该植物中分离得到。该法具有简便、快速的优点。 相似文献
5.
6.
7.
8.
从西藏胡黄连中分离和鉴定了4个化合物,其中化合物1是新化合物,命名为西藏胡黄连酚苷E(Scrophenoside E),结构为(2-甲氧基-4-乙酰基)苯酚-3-β-D-吡喃葡萄糖基-6-O-(4-β-D-吡喃葡萄糖基)香草酰基-β-D-吡喃葡萄糖苷. 相似文献
9.
10.
两头尖化学成分研究 总被引:6,自引:0,他引:6
通过硅胶柱色谱、大孔树脂、反相柱层析及半制备型高效液相色谱等方法,从两头尖根茎中分离得到3种化合物,根据理化性质和光谱分析(ESI-MS、^1HNMR、^13CNMR、HMBC、HMQC、TOCSY、DEFT)鉴定其结构分别为:3-O-α-L-吡喃鼠李糖基-(1→2)-[β-D-吡喃葡萄糖基-(1→4)]-α-L-吡喃阿拉伯糖基齐墩果酸28-β-D-吡喃葡萄糖基-(1→6)-β-D.吡喃葡萄糖酯(I)、3-O-α-L吡喃阿拉伯糖基-(1→3)-O-α-L吡喃鼠李糖基-(1→2)-α-L-吡喃阿拉伯糖基齐墩果酸28-α-L吡喃鼠李糖基-(1→4)-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖酯㈣和3-O-α-L-吡喃鼠李糖基-(1→9)-α-L-吡喃阿拉伯糖基齐墩果酸28-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖酯(Ⅲ),其中化合物Ⅰ、Ⅱ为新化合物,分别命名为多被银莲花皂苷14(Rad-deanoside 14),多被银莲花皂苷15(Raddeanoside 15)。化合物Ⅲ为已知化合物常春藤皂苷B。 相似文献
11.
Fiorentino A D'Abrosca B Pacifico S Golino A Mastellone C Oriano P Monaco P 《Molecules (Basel, Switzerland)》2007,12(2):263-270
One new and six known flavone glycosides were isolated from the MeOH extract of Melilotus neapolitana Ten. The new compound, identified as 7-O-beta-D-glucopyranosyloxy-4',5-dihydroxy-3-[O-alpha-L-rhamnopyranosyl-(1-->6)-3-O-beta-D-glucopyranosyloxy]flavone (1) by 1D and 2D NMR techniques and mass spectra, was isolated along with kaempferol-3-O-rutinoside (2), kaempferol-3-O-glucoside (3), rutin (4), quercetin-3-O-glucoside (5), isorhamnetin-3-O-rutinoside (6), and isorhamnetin-3-O-glucoside (7). The antioxidant and radical scavenging activities of these compounds and the whole crude methanol extract were evaluated. The organic extract can inhibit MDA marker's synthesis by 57%. All the metabolites displayed good reducing power, with the kaempferol (2,3) and isorhamnetin derivatives (6,7) being less active than the corresponding quercetin derivatives 4,5. 相似文献
12.
Al-Musayeib N Perveen S Fatima I Nasir M Hussain A 《Molecules (Basel, Switzerland)》2011,16(12):10214-10226
Nine compounds have been isolated from the ethyl acetate soluble fraction of C. sinensis, namely protocatechuic acid (1), trans-caffeic acid (2), methyl rosmarinate (3), rosmarinic acid (4), kaempferide-3-O-β-D-glucopyranoside (5), kaempferol-3-O-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranoside (7), kaempferide-3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (8) and kaempferol-3-O-α-L-rhamno-pyranosyl (1→6)-β-D-glucopyranoside (9), all reported for the first time from this species. The structures of these compounds were deduced on the basis of spectroscopic studies, including 1D and 2D NMR techniques. Compounds 1-9 were investigated for biological activity and showed significant anti-inflammatory activity in the carrageen induced rat paw edema test. The antioxidant activities of isolated compounds 1-9 were evaluated by the DPPH radical scavenging test, and compounds 1, 2, 4 and 7-9 exhibited marked scavenging activity compared to the standard BHA. These compounds were further studied for their anti-glycation properties and some compounds showed significant anti-glycation inhibitory activity. The purity of compounds 2-5, 8 and 9 was confirmed by HPLC. The implications of these results for the chemotaxonomic studies of the genus Cordia have also been discussed. 相似文献
13.
Activity-guided fractionation of the ethanolic extract of the leaves of the Polyalthia longifolia var. pendula led to the identification of quercetin (1), quercetin-3-O-β-glucopyranoside (2), kaempferol-3-O-α-rhamnopyranosyl-(1 → 6)-β-galactopyranoside (3), kaempferol-3-O-α-rhamnopyranosyl-(1 → 6)-β-glucopyranoside (4), rutin (5) and allantoin (6) as the active constituents from the butanol fraction. Compounds 2-4 are reported for the first time from this natural source. Structures of the compounds were confirmed on the basis of their 1D and 2D NMR coupled with other spectroscopic methods. All the isolated compounds and the fractions were evaluated for their antioxidant potential using the TEAC assays and it was found that the activity of the active fraction was due to quercetin (1) and its glycosides (2 and 5), with TEAC values of 4.10, 1.91 and 2.38 mM, respectively, while the kaempferol glycosides were found to be inactive. This is the first study on the antioxidant activity of this plant species. 相似文献
14.
Negative electrospray ionization tandem quadrupole mass spectrometry was used to study the collision-induced dissociation (CID) of the O-glycosidic bond from different commercially available flavonoid glycosides. Depending on the structure, flavonoid glycosides can undergo both a collision-induced homolytic and heterolytic cleavage of the O-glycosidic bond producing deprotonated radical aglycone ((Y(0) - H)(-*)) and aglycone (Y(0) (-)) product ions. The relative abundance of the radical aglycone to the aglycone fragment from flavonol-3-O-glycosides increased with increasing number of hydroxyl substituents in the B ring and in the order kaempferol - 相似文献
15.
In this study, the chemical constituents of Campanula alliariifolia Willd. (Campanulaceae) are being investigated for the first time with the aid of this article. Five known compounds, which were quercetin-3-O-glucoside, quercetin-3-O-rutinoside, kaempferol-3-O-glucoside, lobetyolin (9-O-beta-D-glucopyranosyl-2,10-tetradecadien-4,6-diyne-8,14-diol) and lobetyol (2,10-tetradecadien-4,6-diyne-8,9,14-triol), were isolated from the methanol extract. The antioxidant activity of the methanol extract and the purified compounds of the plant was investigated with DPPH (1,1-diphenyl-picrilyhydrazyl) (free radical scavenging activity) and reducing power methods. The methanol extract has antioxidant capacity according to the mentioned methods. Lobetyol and lobetyolin showed significant antioxidant activity more than both methanol extract and other purified compounds. 相似文献
16.
Blackcurrant is considered as a natural high-value food raw material and possesses a variety of therapeutic properties. The health benefits of blackcurrant have generally been credited to its high anthocyanin content; however, the therapeutic properties of other minor flavonoids constituents have not yet been investigated due the difficulties related to their isolation. Multiple steps of high-performance counter-current chromatography in combination with ESI tandem mass spectrometry (MS(n)) were successfully used for the preparative isolation of flavonols from blackcurrant extract, to study their electrospray ionization mass spectrometry fragmentation behavior. Seven flavonols, namely myricetin-3-O-rutinoside (145.5 mg), myricetin-3-O-hexoside (79.7 mg), myricetin-3-O-(6″-malonyl)-glucoside (17.4 mg), kaempferol-3-O-glucoside (20.5 mg), quercetin-3-O-rutinoside (55.1 mg), quercetin-3-O-hexoside (25.8 mg), and myricetin (129.1 mg) have been successfully isolated and their multistage MS(n) data were used for detailed structure characterization. The results of these experiments demonstrated that high-performance counter-current chromatography along with ESI-MS(n) is a sensitive, selective, and effective technology for isolation and characterization of minor constituents from a complex mixture. 相似文献
17.
Two new compounds: 3-β,15-α,23,28-tetrahydroxyolean-12-en-3-O-arabinopyaranoside and 3-β,23,28-trihydroxy-olean-12-en-3-O-β-D-glucopyranoside were isolated from the aerial parts of Ammania auriculata along with the known compounds kaempferol, β-sitosterol-3-O-β- D-glucoside, 2-α,3-β,23-trihydroxyolean-12-en-28-oic acid-28-O-β-D-glucopyranoside, quercetin, kaempferol-3-O-α-L-arabinofuranoside, kaempferol-3-O-β-D-xylopyranoside and ellagic acid. Structures of these compounds were elucidated on the basis of their spectroscopic data (NMR, UV, MS and IR spectra). The antioxidant activities of the total extract, the fractions CH(2)Cl(2), EtOAc and the remaining aqueous together with the compounds 1, 6 and 9 were comparable with that of the standard antioxidant, ascorbic acid. 相似文献
18.
Mendiondo ME Juáreza BE Zampini C Isla MI Ordoñez R 《Natural product communications》2011,6(7):965-968
Methanolic extracts of Chuquiraga straminea Sandwith, subfamily Barnadesioideae (Asteraceae) showed the presence of quercetin-3-O-glucoside, quercetin-3-O-rutinoside, kaempferol, kaempferol-3-O-glucoside and kaempferol-3-O-rutinoside. Antioxidant and antimicrobial activity was determined. The total extracts showed antioxidant activity by DPPH and ABTS method (SC50 14.5 to 34.9 microg/mL). A significantly positive correlation was observed between the antioxidant activity and the total phenolics (R2 > 0.93). The extracts were active against ten methicillin resistant and sensitive Staphylococcus aureus strains isolated from nosocomial infection (MIC values between 200 to 800 microg/mL). These preliminary studies are highly interesting as they open new ways for further applications in the treatment of infections by methicillin resistant S. aureus. 相似文献
19.
YuBoWANG ShuangXiMEI YaoHuaWANG JingFengZHAO HaiYingREN JieGUO HongBinZhANG LiangLI 《中国化学快报》2003,14(9):923-925
Two new flavonol glycosides (1 and 2) together with two known flavonoides (3 and 4),were isolated from the whole plant of Knoxia corymbosa willd. The structures of I and 2 were elucidated as kaempferol-7-O-α-L-arabinosyl-3-O-β-D-6“-acetylglucopyranoside and kaempferol -7-O-α-L-arabinosyl-3-O-β-D-3″,6″-diacetylglucopyranoside respectivedly. 相似文献