共查询到20条相似文献，搜索用时 250 毫秒
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中国沙棘叶化学成分的研究(Ⅱ) 总被引：7，自引：0，他引：7
目的：研究中国沙棘叶化学成分。方法：采用硅胶柱层析、Sephadex LH-20凝胶柱层析进行分离，通过理化常数测定和波谱技术进行结构鉴定。结果：从沙棘Hippophae rhanmoides L-叶中分离并鉴定了3个化合物：β-谷甾醇(β-sitosterol，I)，2α-OH-熊果酸(2α-hydroxy-ursolic acid，Ⅱ)，L-2-0-CH3-肌醇(L-2-0-methyl-inositol，Ⅲ)．结论：以上化合物均为首次从中国沙棘叶中分离得到，2α-OH-熊果酸，L-2-0-CH3-肌醇为首次从该属植物中分离得到。 相似文献
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青梅叶化学成分研究 总被引：1，自引：0，他引：1
采用正相硅胶柱、反相硅胶柱、凝胶柱等柱色谱及高效液相色谱等方法对青梅叶的化学成分进行分离纯化,并通过理化性质和核磁共振等方法鉴定化合物的结构。从青梅叶75%乙醇提取物中分离了13个化合物,分别鉴定为岩白菜素(1),1,3,4/2,5-环己五醇(2),3-(1-C-β-葡萄糖)-2,6-二羟基-5-甲氧基苯甲酸(3),木栓酮(4),木栓醇(5),羽扇豆醇(6),4-叔丁基苯甲醚(7),对甲氧基苯甲酸(8),邻苯二甲酸二异丁酯(9),邻苯二甲酸二丁酯(10),熊果酸(11),β-谷甾醇(12),β-胡萝卜苷(13)。化合物2～9均为首次从青梅属植物中分离得到,化合物1为青梅中具有保肝护肝的主要活性成分之一。 相似文献
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SONG Xin-ming CHEN Guang-ying SONG Xiao-ping HAN Chang-ri CHEN Sai-qin WENG Shi-chang 《林产化学与工业》2012,32(3)
采用正相硅胶柱、反相硅胶柱、凝胶柱等柱色谱及高效液相色谱等方法对青梅叶的化学成分进行分离纯化,并通过理化性质和核磁共振等方法鉴定化合物的结构.从青梅叶75％乙醇提取物中分离了13个化合物,分别鉴定为岩白菜素(1),1,3,4/2,5-环己五醇(2),3-(1 -C-β-葡萄糖)-2,6-二羟基-5-甲氧基苯甲酸(3),木栓酮(4),木栓醇(5),羽扇豆醇(6),4-叔丁基苯甲醚(7),对甲氧基苯甲酸(8),邻苯二甲酸二异丁酯(9),邻苯二甲酸二丁酯(10),熊果酸(11),β-谷甾醇(12),β-胡萝卜苷(13).化合物2～9均为首次从青梅属植物中分离得到,化合物1为青梅中具有保肝护肝的主要活性成分之一. 相似文献
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《林产化学与工业》2017,(1)
对小远志化学成分进行研究,从中分离得到12个化合物,依据理化性质及波谱数据分析,分别鉴定为:丁香醛(1),4-羟基-3,5-二甲氧基-苯乙酮(2),8-羟基-1-(4-羟基-3-甲氧基)苯基-1-丙酮(3),水杨酸(4),反式芥子酸甲酯(5),3,4,5-三甲氧基肉桂酸甲酯(6),3,4,5-三甲氧基肉桂酸(7),5-羟基-4',6,7-三甲氧基黄酮(8),芥子醇-4-O-β-D-芹糖-(1→2)-β-D-吡喃葡萄糖苷(9),(±)-丁香脂素(10),(+)-梣皮树脂醇(11),(±)-松脂醇(12)。除化合物4外,其它化合物均为首次从该植物中分离得到。 相似文献
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三花假卫矛三萜类化学成分的研究 总被引：1，自引：1，他引：0
通过核磁共振和质普分析对三花假卫矛藤茎的化学成分进行研究,分离并鉴定了6个三萜类化学成分,分别为β-香树脂醇(Ⅰ)、齐墩果酸(Ⅱ)、β-香树脂醇棕榈酸脂(Ⅲ)、羽扇豆醇(Ⅳ)、20(30)-羽扇豆烯-3-酮(Ⅴ)及20(30)-羽扇豆烯-3β, 29-二醇(Ⅵ)。经检索,所有化合物均为首次从三花假卫矛中分得。 相似文献
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A new megastigmane sesquiterpene glucoside named chaihuxinoside A (1), and a new indole diglucoside named chaihuxinoside B (9) were isolated from the aerial parts of Bupleurum chinense DC. along with eight known compounds. Structures of two new compounds were elucidated by a combination of chemical and spectroscopic methods. Chaihuxinosides A and B were characterized as 11-hydroxyl-4-en-3,9-dioxo- megastigmane-11-O-beta-D-glucopyranoside (1), and 3-carboxy-indole-10-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl ester (9), respectively. 相似文献
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Wood, macromolecular and simple model compounds, were reacted with CrO3 or K2CrO4 aqueous solutions. Extracted lignin, guaiacol, vanillin, vanillyl alcohol and homovanillyl alcohol were chosen as model compounds for lignin, whilst cellulose, gum Ghatti, xylan, extracted hemicellulose from pine, methyl-β-D-glucopyranoside and methyl-β-cellobioside were used as models for wood polysaccharides. The kinetics of the reduction reactions of Cr(VI) were monitored using UV-Vis spectroscopy and the results obtained for several temperatures are discussed. In general terms, wood, lignin and lignin model compounds reduced Cr(VI) faster and to a greater extent than polysaccharides or simple sugar molecules. Moreover, lignin model compounds were reduced even faster than lignin. Simple sugars showed a reduction pattern similar to that of cellulose. Extracted hemicellulose revealed to be a poorer reductant while gum Ghatti was the strongest among the polysaccharides. As expected, CrO3 aq. behaved as a more powerfull oxidant than K2CrO4 aq. for these substances. Even at 100 °C, sugars or polysaccharides did not seem to be oxidised by K2CrO4 aq. 0.01 M. These results suggest that, because of the differences in reactivity, lignin reacts preferentially when wood is treated with Cr(VI)-containing formulations, like those which are applied in wood preservation treatments. 相似文献
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Seiichi Yasuda Eri Hamaguchi Yasuyuki Matsushita Hideyuki Goto Takanori Imai 《Journal of Wood Science》1998,44(2):116-124
Highly condensed lignin can be transformed by three reactions — phenolation, hydroxymethylation, and neutral sulfonation — to water-soluble lignosulfonate. To elucidate reactivities and products in the latter two reactions, simple compounds were selected as lignin model compounds. With hydroxymethylation of creosol at 60°C, the yield of a condensed-type product with the diarylmethane structure was less than 10%. Hydroxymethylation of 1-guaiacyl-1-p-hydroxy-phenylethane (compound VI) as a phenolized guaiacyl lignin model compound gave four compounds. The initial reaction introduced the hydroxymethyl group mainly in the guaiacyl nucleus, and the additional reaction created two hydroxymethyl groups in the p-hydroxyphenyl nucleus. Contrary to our estimation, treatment of the models with 13C-labeled formaldehyde (H13CIIO) did not form any diarylmethane structure. Neutral sulfite treatment of hydroxymethylated products gave corresponding sulfonates in high yields. Phenolized guaiacylglycerol--aryl ether (compound XVI) showed a reactivity similar to that of compound VI.This paper was presented at the 45th and 46th annual meetings of the Japan Wood Research Society at Tokyo and Kumamoto, April 1995 and April 1996, respectively 相似文献
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To examine the effect of the presence of benzylic hydroxyl group on the reaction of β-O-4 type lignin moiety with active oxygen species (AOS) under oxygen bleaching conditions, a specially designed β-O-4 type model compound carrying the benzylic methoxyl group, 2-(3,5-difluorophenoxy)-3-methoxy-3-(3,4-dimethoxyphenyl)propan-1-ol (IV), was treated together with a phenolic compound, 4-hydroxy-3-methoxybenzyl alcohol (II), under oxygen bleaching conditions. In this reaction system, AOS were generated by reactions of compound II with dioxygen and attacked compound IV. Compound IV was rather stable, while an analogous model compound carrying the benzylic hydroxyl group, 2-(3,5-difluorophenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol (I), was rather degraded. This result and the previous knowledge on the relatively high stability of 3,4-dimethoxybenzyl alcohol carrying only the hydroxymethyl group as side-chain under the identical reaction conditions suggested that the existence of benzylic hydroxymethylene group is essential in the extensive reaction of side-chain of β-O-4 type lignin moiety with AOS. To compare the reactivity of AOS toward different types of hydroxyl and aryloxyl carbons, 2-(3,5-difluorophenoxy)propane-1,3-diol (VI) or 3-(3,5-difluorophenoxy)propane-1,2-diol (VII) was also subjected to this reaction system. Compound VII was degraded by AOS more extensively than compound VI. 相似文献
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To examine whether non-phenolic lignin moiety is converted into the new phenolic counterpart by the participation of active oxygen species (AOS) under oxygen bleaching conditions, a β-O-4 type dimeric lignin model compound, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol (I), 2-(3,5-difluorophenoxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol (III), or 2-(3,5-difluorophenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol (IV), was treated under conditions similar to those for oxygen bleaching. A phenolic compound, 4-hydroxy-3-methoxybenzyl alcohol, was added together to generate AOS in the reaction of compound I or IV. The results obtained suggested that AOS attack the side chains of compounds I, III, and IV accompanied by the β-O-4 bond cleavages and the liberations of the corresponding phenolic compounds, 2-methoxyphenol (II), 3,5-difluorophenol (V), and compound V, respectively. However, the rapid liberation of compound V in the oxygen-alkali treatment of compound III may mainly be caused by alkaline-induced reactions and/or some oxidation reactions of the primary degradation product of compound III, a muconic acid derivative. 相似文献
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Cuttings from mature chestnut (Castanea spp.) trees are very difficult to root, whereas juvenile or etiolated cuttings root easily. The HPLC chromatograms from mature cuttings consistently showed two well-defined peaks that were absent from juvenile or etiolated cuttings. The compounds responsible for these two peaks were isolated and identified as derivatives of ellagic acid, 3,3',4-tri-O-methylellagic acid (compound 1) and 3,4,4'-tri-O-methylellagic acid (compound II). Compound I significantly inhibited rooting as measured by the bean test; a concentration of 3.0 x 10(-5) M caused a 32% inhibition in number of roots formed compared with controls grown in 10(-5) M IAA. When compound I was mixed with an equal quantity of IAA, the rooting activity of the auxin was reduced by 31.5%. An insufficient amount of compound II was available for the bean assay. 相似文献
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用RAPD标记进行鹅掌楸杂种识别和亲本选配 总被引：18，自引：4，他引：18
杂种马褂木是以鹅掌楸属 (Ｌｉｒｉｏｄｅｎｄｒｏｎ)现存两个种中国马褂木 (Ｌ .ｃｈｉｎｅｎｓｅ(Ｈｅｍｓｌ.)Ｓａｒｇ .)和北美鹅掌楸 (Ｌ .ｔｕｌｉｐｉｆｅｒａＬ .)为亲本所创造的种间杂种 ,由叶培忠教授于 1 963年首次育成。 30多年的栽培试验表明 ,该杂种不仅在生长和 相似文献
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《Fitoterapia》2013
Mate (Ilex paraguariensis A. St.-Hil) is a native species of South America used to prepare traditional beverages. Recently a possible effect of its infusion on oxidative stress found in dyslipidemias has been reported. The main compounds related to these activities are phenolic compounds derived from chlorogenic acid. This study aimed to determine the anticholesteremic effect of the hydroethanolic extract (HEIP) and its n-butanolic fraction (n-BFIP), with standardized content of phenolic compounds derived from chlorogenic acid, in rats treated with high-fat diet (HFD). The contents of these compounds in the ethanol extract and n-butanol fraction were respectively two and three times higher than in traditional infusion with predominance of dicaffeoylquinic derivatives. The extracts were able to reduce serum triglycerides and cholesterol and decrease the atherogenic index in treated animals. These results support a potential effect of the mate extract in cardiovascular disease. 相似文献
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Yu Wu Ji Zhang Xiao-Juan Jin Jian-Min Gao Qiang Zhao 《Wood Science and Technology》2014,48(4):713-725
Nitrogen-enriched activated carbons were prepared from waste medium density fiberboard waste by using NaOH, K2CO3 and KOH. The content of nitrogen in the activated carbon was 0.92, 0.74 and 1.33 % by analysis. The influence of contact time, pH, Cr(VI) initial concentration and the amount of activated carbon on the Cr(VI) adsorption capacity were investigated. The maximum adsorption capacity of Cr(VI) could reach 89.21 mg/g at pH 2 and a contact time of 9 h. The kinetics adsorption followed nicely the pseudo-second-order rate expression. In adsorption isotherm, the Langmuir model fitted better than the Freundlich model. Pure Poplar activated carbon was also prepared as the adsorbent for Cr(VI) removal as control sample. This study indicated that the nitrogen-enriched activated carbon prepared from waste medium density fiberboard can be used effectively for the removal of Cr(VI) compound from aqueous solutions. 相似文献