中药翻白草黄酮类化学成分及其降糖活性研究

以翻白草为材料,探究黄酮类化学成分及其降糖活性降糖活性。采用系统溶剂法、柱色谱分离法对翻白草的化学成分进行分离,并鉴定化合物结构。基于HepG2细胞,筛选出具有降糖活性的化合物;采用胰岛素抵抗模型,筛选具有改善胰岛素抵抗的化合物。从翻白草乙醇提取物中分离得到13个化合物,分别鉴定为芹菜素(1)、木犀草素(2)、山柰酚(3)、山柰酚-3-O-β-D-吡喃葡萄糖苷(4)、山柰酚-3-O-β-D-葡萄糖醛酸苷(5)、山柰酚-3-O-β-D-半乳糖苷(6)、山柰酚-3-O-ɑ-L-阿拉伯糖苷(7)、槲皮苷(8)、槲皮素-3-O-β-D-吡喃葡萄糖苷(9)、槲皮素-7-O-β-D-吡喃葡萄糖苷(10)、槲皮素-3-O-β-D-葡萄糖醛酸苷(11)、异鼠李素(12)、异鼠李素-3-O-β-D-葡萄糖醛酸苷(13)。正常HepG2细胞实验中,化合物3、4、11、12、13组葡萄糖含量显著下降(P0.05);胰岛素耐受细胞实验中,化合物3、9、11、13组葡萄糖含量显著下降(P0.05),化合物3、13组的PPARγ蛋白表达显著上升(P0.05)。化合物3、4、11、12、13能够促进正常的HepG2细胞葡萄糖消耗,化合物3、9、11、13能够改善胰岛素抵抗的HepG2细胞葡萄糖消耗。     

龙眼核中的神经酰胺和脑苷脂的分离和鉴定

研究龙眼(Dimocarpus longan Lour.)果核的化学成分,采用硅胶柱色谱对龙眼果核石油醚提取物和体积分数95%乙醇提取物进行分离,并利用理化性质和光谱数据鉴定化合物的结构。从龙眼果核的提取物中分离得到一组混合神经酰胺(化合物1、2)和一组混合脑苷脂(化合物3～6),结构鉴定为Rel-(3S,4S,5S)-3-[(2'R)-2'-羟基二十二酰胺]-4-羟基-5-[(4″Z)-十四烷-4″-烯]-2,3,4,5-四氢呋喃(1)、Rel-(3S,4S,5S)-3-[(2'R)-2'-羟基二十四酰胺]-4-羟基-5-[(4″Z)-十四烷-4″-烯]-2,3,4,5-四氢呋喃(2)、1-O-(β-D-吡喃葡萄糖基)-(2S,3S,4R,8E)-2-(2'-羟基二十四酰胺)-8-十八烯-1,3,4-三醇(3)、1-O-(β-D-吡喃葡萄糖基)-(2S,3S,4R,8Z)-2-(2'-羟基二十四酰胺)-8-十八烯-1,3,4-三醇(4)、1-O-(β-D-吡喃葡萄糖基)-(2S,3S,4R,8E)-2-(2'-羟基二十二酰胺)-8-十八烯-1,3,4-三醇(5)、1-O-(β-D-吡喃葡萄糖基)-(2S,3S,4R,8Z)-2-(2'-羟基二十二酰胺)-8-十八烯-1,3,4-三醇(6)。     

一支箭黄酮类化学成分研究

采用硅胶柱色谱、凝胶色谱及高压制备色谱等方法对一支箭(Ophioglossum vulgatum Linn.)的黄酮类成分进行分离纯化和结构表征.共分离得到黄酮类化合物5个,分别为3-O-甲基槲皮素7-O-β-D-葡萄糖基-4′-O-β-D-葡萄糖苷(1),槲皮素3-O-(6-O-咖啡酰基)-β-D-葡萄糖基-(1→2...     

新疆白麻药用成分的提取与表征

以新疆白麻Poacynum pictum(Schrenk)Baill叶为原料,采用溶剂萃取及色谱技术从新疆白麻叶中共分离并鉴定了11个化合物的结构,并通过理化常数、MS、1H NMR和13C NMR等现代波谱技术鉴定其化学结构,分别为羽扇醇棕榈酸酯(1)、异莨菪亭(2)、正十六烷酸(3)、正二十六烷酸(4)、β-谷甾醇(5)、槲皮素(6)、槲皮素-3-O-β-D-吡喃葡萄糖苷(7)、金丝桃苷(8)、Δ′-异戊烯-3-O-β-D-吡喃葡萄糖苷(9)、丁香树脂醇-β-D-吡喃葡萄糖苷(10)和蔗糖(11)。其中化合物2为首次从属中分离得到。     

葫芦茶乙酸乙酯部位化学成分研究

研究葫芦茶(Tadehagi Triquetrum)的化学成分。通过各种柱色谱方法分离纯化,利用波谱技术分析确定化合物的结构。从葫芦茶乙醇提取物的乙酸乙酯部位中分离得到10个化合物,分别鉴定为:山奈酚(1),槲皮素(2),香草酸(3),葫芦茶苷(4),顺式葫芦茶苷(5),槲皮素-3-O-β-D-吡喃葡萄糖苷(6),山奈酚-3-O-β-D-吡喃半乳糖苷(7),山奈酚-3-O-α-L-吡喃鼠李糖苷(8),山奈酚-3-O-β-D-吡喃葡萄糖苷(9),原儿茶酸(10)。化合物9和10为首次从该植物分离得到。     

皇冠果籽化学成分的分离提取

对皇冠果籽进行了化学成分的分离提取,从中得到了8个化合物,分别是十四碳酸、软脂酸、硬脂酸乙脂、β-胡萝卜苷、4,4’-二羟基-2-甲氧基二苯甲酮-6-O-β-D-葡萄糖苷、山奈酚-3-O-β-D-葡萄糖苷、芒果素、蔗糖.其中4,4’-二羟基-2-甲氧基二苯甲酮-6-O-β-D-葡萄糖苷为首次报道的新化合物。     

洋甘菊中黄酮类成分的分离与结构确定

对洋甘菊中黄酮类活性成分进行分离纯化和结构确定。经过聚酰胺反复柱色谱进行分离、纯化,并经核磁共振确定其结构。从洋甘菊的乙醇(95%)提取物中分离得到2个黄酮类化合物,其结构被确定为芹菜素-7-O-β-D-葡萄糖苷(Ⅰ)和木犀草素-7-O-β-D-葡萄糖苷(Ⅱ)。芹菜素-7-O-β-D-葡萄糖苷和木犀草素-7-O-β-D-葡萄糖苷很可能为洋甘菊的主要黄酮活性成分。     

水蓼化学成分的研究

目的:研究水蓼的化学成分。方法:应用硅胶、MCI、Sephadex LH-20、RP-18柱色谱进行分离、纯化,根据理化常数和光谱分析鉴定结构。结果:从水蓼提取物中分离鉴定了9个单体化合物:β-谷甾醇(1),熊果酸(2),槲皮素(3),槲皮苷(4),芦丁(5),山奈酚-3-O-β-D-葡萄糖苷(6),绿原酸(7),咖啡酸(8),金丝桃苷(9)。结论:化合物6、7、8为首次从水蓼中分离鉴定。     

刺齿贯众化学成分的研究

从鳞毛蕨科植物刺齿贯众(Cyrtomium caryotideum)地上部分通过溶剂提取、硅胶柱层析、SephadexLH-20柱层析和MCI柱层析等方法分离得到4个化合物,经核磁共振氢谱、碳谱和质谱确定了它们的结构,分别为山奈酚-3-O-β-D-葡萄糖苷(1)、山奈酚-3-O-β-D-芸香糖苷(2)、大黄素(3),5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(4)。化合物3和4为首次从本植物中分离得到。     

都匀楼梯草正丁醇和石油醚部位化学成分的研究

采用柱色谱分离技术,在都匀楼梯草(Elatostema duyunens)正丁醇和石油醚部位中分离得到18个化合物,通过MS和NMR数据分析,鉴定出10个化合物,分别为:槲皮素(1)、槲皮素-3-O-β-D-半乳糖苷(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、山奈酚(4)、山奈酚-3-O-β-D-葡萄糖苷(5)、齐墩果酸(6)、β-谷甾醇(7)、熊果酸(8)、豆甾醇(9)和正二十五烷(10)。     

毛杜仲藤中神经酰胺类化合物的分离与结构鉴定

用硅胶,重结晶等手段进行分离纯化,根据化合物的理化性质和光谱数据鉴定结构,来研究毛杜仲藤的化学成分.结果分离得到一个神经酰胺类混合物(化合物1-4),即N-(2'-羟基二十一碳酰基)-1,3,4-三羟基-2-氨基-△8,9(E)-十八碳烯,N-(2'-羟基二十二碳酰基)-1,3,4-三羟基-2-氨基-△8,9(E)-十...     

HS-SPME/GC-MS法分析香椿芽、叶的挥发性化学成分

采用顶空固相微萃取/气相色谱-质谱(HS-SPME/GC-MS)联用技术分析香椿芽、叶的挥发性化学成分,用峰面积归一化法测定了各挥发性物质的相对质量分数。结果表明:从香椿芽萃取物中鉴定出26个成分,占挥发性组分总质量的74.86%,主要成分是β-石竹烯(质量分数,下同,10.12%),2-氮杂环丙烷乙基胺(10.09%),2-氨氧基丙酸(10.03%),β-香柠檬烯(8.78%),桉-4(14),11-二烯(6.59%),α-荜澄茄油烯(3.02%),α-雪松烯(2.88%),罗勒烯(2.69%),8-异丙烯基-1,5-二甲基-1,5-环癸二烯(2.36%),2-羟基乙基联氨(2.10%),丙基柏木醚(2.07%),羟基乙醛(1.88%),环癸烷醇(1.63%),外-葑醇(1.54%),1,3,8-对?三烯(1.46%),α-姜黄烯(1.18%);从香椿叶萃取物中鉴定出46种成分,占挥发性组分总质量的91.2%,主要成分是β-石竹烯(46.87%),(E)-2-己烯醛(5.29%),α-石竹烯(4.12%),8-异丙烯基-1,5-二甲基-1,5-环癸二烯(3.96%),β-香柠檬烯(3.48%),桉-4(14),11-二烯(3.37%),α-荜澄茄油烯(3.23%),β-波旁烯(2.41%),2-氮杂环丙烷乙基胺(2.23%),α-法呢烯(1.42%),异石竹烯(1.22%),β-萜烯(1.03%)。     

β-取代卟啉及卟啉锰对氧化破坏的稳定性

在假一级条件下,以亚碘酰苯为氧化剂,通过测定β-未取代的四苯基卟啉(TPP),以及不同β-取代的β-Cl8TPP、β-Br8TPP、β-Br4TPP、β-NO2TPP、β-(CH3)8TPP及其金属锰配合物的氧化破坏反应的表观动力学常数,获得了卟啉配体的稳定性顺序为TPP>β-(CH3)8TPP>β-Br8TPP>β-Cl8TPP>β-Br4TPP>β-NO2TPP,β位位阻越大相应的卟啉配体越稳定,并由此推导PhIO由β位进攻卟啉配体。β-取代锰卟啉的稳定性顺序为:Mn(β-Cl8TPP)Cl>Mn(β-Br8TPP)Cl>Mn(β-Br4TPP)Cl>Mn(β-NO2TPP)Cl>Mn(TPP)Cl>Mn[β-(CH3)8TPP]Cl,并与在催化氧化环己烷反应中的稳定性一致,β位吸电子作用越大相应的锰卟啉越稳定,并推导由氧化能力更强的高价金属-氧中间体以位阻较小的面对面方式进攻β-取代锰卟啉。     

Kinetic studies on lipase-catalyzed acetylation of 2-alkanol with vinyl acetate in organic solvent

Lipase-catalyzed acetylation of 2-alkanol with vinyl acetate has been studied kinetically using Burkholderia cepacia lipase (BCL), enantiomerically pure (R)- and (S)-2-alkanols and different organic solvents. The rate equation was derived by the steady state method for the simplified mechanism. The second order rate constants (k(R) and k(S)) for (R)- and (S)-2-alkanols were evaluated from the slopes of the double reciprocal plots, v(-1) vs. [2-alkanol](-1), where v is the initial rate of the reaction. The log k(R) value increased with the solvent hydrophobicity log P, where P is a partition coefficient of a given solvent between octanol and water. The log k(S) value also increased with log P except the bulky solvents such as 1,4-dioxane and cyclohexane, in which the rates were faster than those expected from the log k(S) vs. log P plot. The slope of log k(S) vs. log P plot was larger than that for (R)-2-alkanol. Thus, log E (E=k(R)/k(S): enantioselectivity) decreased with log P except the bulky solvents. The rate constants and the enantioselectivity were different depending on the structure (carbon number CN) of 2-alkanol. The log E vs. CN plot was minimized at CN=8 and 10 and the log k(S) vs. CN plot maximized at CN=8 and 10. In contrast the log k(R) vs. CN plot showed a different feature from the log E vs. CN plot. These facts suggest that dependence of E on CN is more strongly affected by the reactivity of (S)-2-alkanol than that of (R) isomer in this acetylation.     

Die Reaktion von α,β-Dihalogen-propionitrilen mit monosubstituierten Hydrazinen - einfache Synthese 1-substituierter 3- bzw. 5-Amino-pyrazole

The Reaction of α,β-Dihalogeno-propionitriles with Monosubstituted Hydrazines — A Simple Synthesis of 1-Substituted 3- or 5-Amino-pyrazoles In methanol hydrazines 3 , and α,β-dihalogeno-propionitriles 1, 2 even at 0°C irreversibly yield 3 · HX, and α-halogenoacrylonitriles 4, 5 (A₁). Fast addition of alkyl- and aralkyl- hydrazines 3 to 4, 5 (C) gives 1-substituted 1-(2′-halogeno-2′-cyan-ethyl)-hydrazines 6 , the addition of arylhydrazines 3 to 4, 5 (D) 1-aryl-2-(2′-halogeno-2′-cyan-ethyl)-hydrazines 8 . In methanol 6 spontaneously cyclise (E) to hydrogen halides 7 · HX of 1-alkyl- and 1-aralkyl-3-amino-pyrazoles, 8 with 2 moles of acids (F) to salts 10 · 2HY of 1-aryl-4-halogeno-5-imino-pyrazolidines, and the free 10 spontaneously (G) to hydrogen halides 9 · HX of 1-aryl-5-amino-pyrazoles. Mechanisms (A₁), (C), (D), (E), (F), and (G) are proved by t.l.c., ¹H-n.m.r., and isolation of intermediates, the structures of 7 resp. 9 , using the significant ¹H-n.m.r.-parameter Δ. Simple general syntheses are described for 3-amino-pyrazoles 7 (R = H, alkyl, aralkyl) or 5-amino-pyrazoles 9 (R = aryl) starting with α,β-dihalogeno-propionitriles 1, 2 , and for α-bromo-acrylonitrile 5 .     

Intermediates of Prostanoid Synthesis. Stereospecific conversion of (+)-5β-hydroxycyclopenten-2-yl-1β-acetic acid γ-lactone into (+)-1β-methoxycarbonylmethyl-2β,3β-(p-nitrobenzylidene)-dioxycyclopentan-5-one

Starting from (+)-5β-hydroxycyclopenten-2-yl-1β-acetic acid γ-lactone ( 1 ), (+)-1β-methoxycarbonylmethyl-2β, 3β-(p-nitrobenzylidene)-dioxycyclopentan-5-one ( 7 ) was prepared within 4 steps. Subsequent cleavage of the latter gives (−)-3β-hydroxy-1-methoxy-carbonylmethylcyclopent-1-en-5-one ( 8a ). Hydroxylation of the lactone ( 1 ) was found to give (+)-2β,3β,5β-trihydroxycyclopentyl-1β-acetic acid γ-lactone ( 2a ) with cis-oriented hydroxy groups in respect to the lactone ring. No formation of the trans-isomer, as has been reported earlier [4], was observed.     

Partialsynthesen von Cardenoliden und Cardenolid-Analogen. VI. (20R)- und (20S)-Cardanolide

Partial Syntheses of Cardenolides and Cardenolide Analogues. VI. (20R)- and (20S)-Cardanolides (20R)-Dihydrodigitoxigenin ( 2 ) and (20S)-dihydrodigitoxigenin ( 4 ) as well as their 3-acetates 3 and 5 , respectively, were synthesized by catalytic hydrogenation of the appropriate cardenolides and separation by column chromatography on silica of the mixtures of stereoisomers. Hydroxymethylation of 3 and 5 followed by selective elimination yielded (20S)- and (20R)-14-hydroxy-22-methylene-5β,14β-cardanolide 3-acetate ( 10 and 16 ), respectively. The biological activities of the synthesized 20-stereoisomeric cardanolides are investigated and discussed. Cardanolides 10 and 16 have a strong inhibitory activity on the proliferation of Ehrlich ascites carcinoma cells in suspension culture.     

Strukturelle Abwandlungen an N-Acetylneuraminsäure. 22 [1]. Zur Umsetzung von Methyl-5-acetamido-7,8-anhydro-4-O-t-butyldimethylsilyl-3,5-didesoxy-D-glycero- und L-glycero-β-D-galakto-nonulopyranosidonsäure-methylester mit Bis-imidazolylthiocarbonat

Structural Variations on N-Acetylneuraminic Acid. 22 On the Reaction of Methyl[5-Acetamido-7,8-anhydro-4-O-t-butyldimethylsilyl-3, 5-dideoxy-D-glycero-and-L-glycero-β-galacto-2-nonulopyranosid]onate with Diimidazolylthiocarbonate The title compounds 1 and 3 are transformed with diimidazolylthiocarbonate into the cyclic 8(S),9(O)-dithiocarbonatosialic acid derivatives 2 and 4 as well as into a mixture of the cyclic 8(S),9(O)-monothiocarbonato derivatives 5a and 5b , which turned with acetanhydride pyridine to the corresponding 4-O-t-butyldimethylsilyl-7-O-acetyl- and 4,7-di-O-acetyl derivatives 5c and 5d .     

A new ceramide from the basidiomycete Russula cyanoxantha

A new phytosphingosine-type ceramide (1) was isolated along with nine other compounds-5alpha,8alpha-epidioxy(22E,24R)-ergosta-6,22-dien-3beta-ol, 5alpha,8alpha-epidioxy-(24S)-ergosta-6-en-3beta-ol, (24S)-ergosta-7-ene-3beta,5alpha,6beta-triol, (22E,24R)-ergosta-7,22-dien-3beta,5alpha,6beta-triol, inosine, adenine, L-pyroglutamic acid, fumaric acid, and D-allitol from the ethanol and chloroform/methanol extract of the fruiting bodies of the basidiomycete Russula cyanoxanotha (Schaeff.) Fr. The structure of (1) was established as (2S,3S,4R,2'R)-2-(2'-hydroxytetracosanoylamino) octadecane-1,3,4-triol by means of spectroscopic and chemical methods.