天山大黄的化学成分研究(Ⅱ)

目的:对天山大黄的化学成分进行研究。方法:用色谱法和光谱分析法分离和鉴定其化学成分。结果:从天山大黄根乙醚和乙酸乙酯部分中分得5个芪类化合物和1个色原酮类化合物,结构分别为trans3,5二羟基4′甲氧基芪,trans3,5,4′三羟基芪,trans3,5,4′四羟基芪,trans3,5,二羟基4′甲氧基芪3OβD葡萄糖甙,trans3,5,3′,4′四羟基芪4′OβD葡萄糖甙和2,5二甲基7羟基色原酮。结论:这些化分物均为首次从该植物中分离得到     

翻白叶树根化学成分的研究

目的：研究梧桐科翅子树属植物翻白叶树Pterospermum heterophyllum根的化学成分。方法：利用硅胶和葡聚糖凝胶等色谱技术进行分离纯化，根据NMR，MS等波谱数据和理化性质鉴定化合物的化学结构。结果：从翻白叶树根95％乙醇提取物的石油醚部分分离和鉴定了9个化合物，分别为：蒲公英萜醇(1)，白桦脂醇(2)，白桦脂酸(3)，苏门树脂酸(4)，2-甲氧基-5-羟基1，4-萘醌(5)，5，7-二羟基-6，8-二甲基色原酮(6)，α-棕榈精(7)，棕榈酸(8)，β-谷甾醇(9)。结论：化合物2～7为首次从该属植物中分得。     

A new chromone from Cassia nodosa

A new chromone named as 5,4′-dihydroxy-7-methyl 3-benzyl chromone (1) along with three known flavonoid compounds as unsubstituted flavone, kaempferol-3-o-rhamnoside and quercetin-3-o-arabinoside have been isolated from the leaves of Cassia nodosa. Their structures have been established by means of chemical and spectral evidences (IR, UV, ¹H-NMR, ¹³C-NMR and mass spectra).     

防风化学成分的研究

目的:对防风Saposhnikovia divaricata未抽花茎的干燥根的化学成分进行研究。方法:采用硅胶柱色谱方法进行分离、纯化,IR,UV,MS和NMR等谱学方法进行结构鉴定。结果:从防风甲醇提取物中得到18个化合物,分别鉴定为3′-O-当归酰亥茅酚(1),异香柑内酯(2),欧前胡素(3),二十五烷酸(4),川白芷内酯(5),紫花前胡素(6),5-甲氧基-7-(3,3-二甲基烯丙氧基)-香豆素(7),紫花前胡醇当归酰酯(8),花椒毒酚(9),香柑内酯(10),杨芽黄素(11),东莨菪素(12),亥茅酚(13),防风色原酮(14),升麻素(15),亥茅酚苷(16),5-O-甲基维斯阿米醇苷(17),升麻苷(18)。结论:化合物2,6~8和11为首次从防风中得到。1,13~18等为色原酮类化合物;化合物2,3,5~10,12等为香豆素类化合物;4为脂肪酸类化合物;11为黄酮类化合物。     

白木香离体根液体培养条件优化及色酮类物质诱导

目的:建立稳定有效的白木香离体根培养体系。方法:考察生长素处理、MS培养基浓度以及初始接种量等因素对白木香离体根培养的影响;用GC-MS技术检测茉莉酸甲酯处理后白木香离体根的色酮类物质成分。结果:单因素实验结果表明,IBA 1.5 mg/L诱导7 d可生成大量生长良好的侧根;MS培养基减量浓度(1/4、1/2、3/4MS)有利于侧根诱导,正常浓度MS有利于侧根生长;每瓶接种15条根为最佳初始接种量。白木香离体根经IBA诱导6 d后开始形成侧根原基,撤去激素后侧根原基迅速增多,18 d后再无新原基生成,最终主根段上可稳定形成12～15条侧根。GC-MS检测结果表明,白木香离体根经过100μmol/L茉莉酸甲酯处理不同时间可产生2-(2-苯乙基)色酮类物质,且产生色酮类物质的种类与刺激时间呈正相关趋势。结论:本研究建立了白木香离体根培养技术体系,为深入探讨色酮类有效物质的次生代谢奠定了基础。     

基于防风外观性状和内在指标性成分划分防风药材商品规格等级研究

目的通过文献、市场及产地调研形成新的防风Saposhnikovia divaricate商品规格等级划分表,根据防风外观性状及与品质相关的内在指标性成分,通过统计学分析,特征图谱比较,探讨新的防风药材商品规格等级划分的科学性和实用性。方法采集黑龙江、吉林、内蒙古、河北等主产区以及主流药材市场上不同规格等级的防风药材样品,根据新的规格等级的划分表,测定样品的外观性状、浸出物、升麻素、升麻素苷、亥茅酚苷、5-O-甲基维斯阿米醇苷的特征图谱,通过统计分析方法,研究规格等级与外观性状及内在指标性成分的关系。结果依照外观性状将防风划分为野生、栽培、仿野生防风3个规格有一定科学依据,同时建议增加升麻素的含量指标作为区分野生防风和栽培防风的指标性成分。结论不同规格的防风药材在外观性状及内在指标上均有显著差异,不同等级的防风药材是否仅以大小作为划分依据还有待讨论。     

Effects of Inclusion Complexation on the Transepithelial Transport of a Lipophilic Substance in Vitro

Poor oral biovailability of three experimental compounds, I ~ III, observed in animals has been attributed to the low intrinsic solubility. To enhance their GI absorption, we attempted to increase the solubility of these compounds with hydroxypropyl -cyclodextrin (HPB)⁴ and -cyclodextrin (HPG). Compound I showed an increase in solubility over 1,000-fold with 25% HPB at 25°C. The association constant of the 1:1 complex between I and HPB was determined by phase-solubility analysis. Thermodynamic parameters involved were all favorable for the complexation. The large positive S° observed suggests that the complex formation is. driven by a hydrophobic interaction. Apical-to-basal transport of I across the Madin Darby canine kidney (MDCK) cell monolayer was studied at 37°C in the presence of HPB with or without agitation. The complex itself did not pass through the cell layer. Diffusion of the unbound I as well as the complex through the aqueous boundary layer in the apical side is rate-limiting. Regardless of hydrodynamics, decreasing HPB concentration at a given drug concentration increased the transport rate. The findings indicate that the transepithelial transport is attributed to the passive diffusion of available free drug molecules rather than the collision complex transfer at the cell surface.     

Several chromones from the stems of Polygonum aubertii Henry

Two new 2-alkylchromanones, 2-tricosyl-2,5,7-trihydroxy-chromanone (6) and 2-pentacosyl-2,5,7-trihydroxy-chromanone (7), together with five known 2-alkylated chromones and chromanones (1–5), were isolated from the stems of Polygonum aubertii Henry. The structures of these compounds were established by spectroscopic methods including extensive 1D, 2D NMR (¹H-¹H COSY, HSQC, and HMBC), and HR-ESI-MS techniques. In addition, a plausible biosynthetic pathway for these compounds is described.     

铁刀木中一个新的色酮苷

目的 研究铁刀木的化学成分。方法 利用硅胶柱色谱和薄层色谱分离铁刀木的化学成分,通过理化常数测定和波谱分析等鉴定化合物的结构。结果从铁刀木树干中分离并鉴定了5个化合物,其结构分别鉴定为:β-谷甾醇(I),蔗糖(II),正二十八醇(III),2-甲基-5-(2′-羟丙基)-7-羟基色酮-2′-O-β-D-吡喃葡糖苷(IV),3,3′,4,5′-四羟基二苯乙烯(V)。结论化合物II,III,V为首次从该植物中分得,化合物IV为新化合物。     

芦荟色酮的研究概况

芦荟色酮是芦荟中重要的一类生物活性物质，近年来由于其抗炎、抗氧化及抑制酪氨酸激酶的活性受到了人们的广泛关注。相对于芦荟中的其他成分而言，关于芦荟色酮的研究，国内外开展还较少。现对芦荟色酮成分、药用价值、提取分离和分析方法进行了综述。