预知子化学成分研究

 目的研究预知子的化学成分。方法通过反复硅胶柱色谱、ODS柱色谱和重结晶的方法分离纯化,根据化合物的理化性质和波谱数据鉴定结构。结果分离得到7个化合物,分别为常春藤皂苷元-3-O-α-L-吡喃鼠李糖基(1→2)-α-L-吡喃阿拉伯糖苷(Ⅰ),常春藤皂苷元-3-O-α-L-吡喃阿拉伯糖苷(Ⅱ),3-O-α-L-吡喃鼠李糖-(1→2)-α-L-吡喃阿拉伯糖-常春藤皂苷元-28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(Ⅲ),3-O-α-L-吡喃阿拉伯糖-常春藤皂苷元-28-O-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(Ⅳ),常春藤皂苷元-28-O-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(Ⅴ),3-O-β-D-吡喃葡萄糖-(1→2)-α-L-吡喃阿拉伯糖-30-去甲齐墩果酸-28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(Ⅵ),胡萝卜苷(Ⅶ)。结论其中化合物Ⅱ、Ⅲ、Ⅳ为首次从本植物中分离得到,化合物Ⅴ、Ⅵ为首次从本属植物中分离得到。     

白木通化学成分研究(Ⅱ)

 目的研究白木通藤茎的化学成分。方法通过反复硅胶柱色谱、ODS柱色谱和重结晶的方法分离纯化,根据化合物的理化性质和波谱数据鉴定结构。结果分离得到5个化合物,分别为2α,3,β23,29-tetrahydroxyolean-12-en-28-oic acid(Ⅰ),齐墩果酸-3-O-β-D-吡喃葡萄糖-(1→3)-α-L-吡喃阿拉伯糖苷(Ⅱ),齐墩果酸-3-O-β-D-吡喃葡萄糖-(1→2)-α-L-吡喃阿拉伯糖苷(Ⅲ),3-O-β-D-glucopyranosyl-(1→2)-α-L-arabino pyranosyl-30-norolean-12-en-28-oic acid(Ⅳ),3-O-β-D-葡萄糖-(1→3)-α-L-阿拉伯糖-常春藤皂苷(Ⅴ)。结论5个化合物均为首次从本植物中分离得到。     

大叶冬青的三萜皂苷类成分研究

 目的 对中药苦丁茶主要品种大叶冬青叶的三萜皂苷类成分进行研究。方法 采用硅胶、葡聚糖凝胶LH-20和反相ODS柱色谱分离大叶冬青叶的水提物,通过光谱分析结合理化性质鉴定化合物的结构。结果 从大叶冬青的水提液中分离得到11个化合物,分别鉴定为α-苦丁内酯3-O-β-D-吡喃葡萄糖(1→3)[α-L-吡喃鼠李糖(1→2)]-α-L-吡喃阿拉伯糖苷(Ⅰ)、α-苦丁内酯3-O-β-D吡喃葡萄糖 (1→2)-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖苷 (Ⅱ)、3-O-β-D-吡喃葡萄糖 (1→2)-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖斯阿树脂酸28-α-L-吡喃鼠李糖 (1→2)-β-D-吡喃葡萄糖酯苷(Ⅲ)、3-O-β-D-吡喃葡萄糖(1→2)-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖坡模醇酸28-α-L-吡喃鼠李糖 (1→2)-β-D-吡喃葡萄糖酯苷 (Ⅳ)、β-苦丁内酯3-O-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖苷(Ⅴ)、β-苦丁内酯3-O-β-D-吡喃葡萄糖 (1→2)-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖苷(Ⅵ)、γ-苦丁内酯3-O-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖苷(Ⅶ)、3-O-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖齐墩果酸28-α-L-吡喃鼠李糖 (1→2)-β-D-吡喃葡萄糖酯苷(Ⅷ)、3-O-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖斯阿树脂酸28-α-L-吡喃鼠李糖 (1→2)-β-D-吡喃葡萄糖酯苷(Ⅸ)、3-O-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖-(1→2)]-α-L-吡喃阿拉伯糖坡模醇酸28-α-L-吡喃鼠李糖 (1→2)- β-D-吡喃葡萄糖酯苷(Ⅹ)及δ-苦丁内酯3-O-β-D-吡喃葡萄糖 (1→2)-β-D-吡喃葡萄糖 (1→3)-[α-L-吡喃鼠李糖 (1→2)]-α-L-吡喃阿拉伯糖苷(Ⅺ)。结论 化合物Ⅰ～Ⅳ、Ⅵ、Ⅶ及Ⅺ为首次从该植物中分离得到。     

过山蕨中黄酮类成分的研究

 目的研究过山蕨(Camptosorus sibiricus Rupr.)中黄酮类化学成分。方法采用反复硅胶柱色谱法、Sephadex LH-20柱色谱法、高效液相色谱法等进行分离纯化,并通过理化常数测定和光谱分析鉴定了其化学结构。结果从过山蕨70%乙醇提取物中分离得到6个黄酮类化合物,并鉴定其结构为:山柰酚(1);山柰酚-7-O-α-L-鼠李糖苷(2);山柰酚-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖苷(3);山柰酚-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-7-O-β-D-吡喃葡萄糖苷(4);山柰酚-3-O-β-D-吡喃葡萄糖基-7-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖苷(5);山柰酚-3-O-β-D-吡喃葡萄糖基(1→4)-α-L-鼠李糖基-7-O-α-L-鼠李糖苷(6)。结论化合物2,3,4,5,6均为首次从该属植物中分离得到。     

地乌中的三萜皂苷类成分

目的：研究地乌Anemone flaccida中的化学成分。方法：采用硅胶柱色谱、凝胶柱色谱、反相HPLC制备色谱等多种方法分离化合物，采用波谱方法鉴定化合物的结构。结果：从地乌根茎中分离得到12个三萜类化合物，分别为齐墩果酸(1)，齐墩果酸3-O-β-D-吡喃葡萄糖-(1→2)-β-D-吡喃木糖苷(2)，五加苷K(3)，齐墩果酸3-O-α-L-吡喃鼠李糖-(1→2)-β-D-吡喃木糖苷(4)，齐墩果酸3-O-β-D-吡喃葡萄糖-(1→2)-α-L-吡喃阿拉伯糖苷(5)，齐墩果酸3-O-βD--吡喃葡萄糖醛酸(6)，齐墩果酸3-O-β-D-吡喃葡萄糖醛酸甲酯(7)，齐墩果酸28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(8)，齐墩果酸3-O-β-D-吡喃葡萄糖醛酸28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(9)，齐墩果酸3-O-β-D-吡喃葡萄糖醛酸甲酯28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(10)，齐墩果酸3-O-β-D-吡喃葡萄糖-(1→2)-β-D-吡喃木糖28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(11)，齐墩果酸3-O-α-L-吡喃鼠李糖-(1→2)-α-L-吡喃阿拉伯糖28-O-α-L-吡喃鼠李糖-(1→4)-β-D-吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖苷(12)。结论：化合物5～8，10,12为首次从该植物中分离得到；化合物2,5,11对Hela,BEL-7402和HL-60细胞具有细胞毒性。     

滇重楼的抗肿瘤活性成分研究

目的：研究滇重楼Paris polyphylla Smith var. yunnanensis根茎中具有抗肿瘤作用的活性成分。方法：利用硅胶柱色谱,Sephadex LH-20,反相制备HPLC等手段进行分离纯化,并通过波谱技术进行结构鉴定。采用MTT法对分离到的化合物进行抗肿瘤活性筛选。结果：从醋酸乙酯和正丁醇层中分离得到了6个化合物,鉴定为薯蓣皂苷元-3-O-α-L-呋喃阿拉伯糖基(1→4)-β-D-葡萄糖苷(1)、偏诺皂苷元-3-O-α-L-呋喃阿拉伯糖基(1→4)-β-D-葡萄糖苷(2)、异鼠李素-3-O-β-D-葡萄糖苷(3)、乙基-α-D-呋喃果糖苷(4)、偏诺皂苷元-3-O-α-L-吡喃鼠李糖基(1→4)-［α-L-吡喃鼠李糖基(1→2)］-β-D-葡萄糖苷(5)、偏诺皂苷元-3-O-α-L-吡喃鼠李糖基(1→4)-α-L-吡喃鼠李糖基(1→4)-［α-L-吡喃鼠李糖基(1→2)］-β-D-葡萄糖苷(6)。结论：化合物1～4为首次从滇重楼中分离得到,化合物3和4为首次从重楼属植物中分离得到,化合物5为首次从滇重楼的根茎中分离得到。药理实验表明,化合物1～3,5和6对小鼠肺腺癌细胞LA795都显示出一定的抑制作用,其中化合物5和6最显著。     

穿山龙中甾体皂苷的分离鉴定

 目的分离、鉴定穿山龙即穿龙薯蓣(Dioscorea nipponica Makino)根茎中的甾体皂苷类化合物。方法采用溶剂提取、硅胶柱色谱及制备高效液相色谱等方法进行分离,通过化学和光谱学方法鉴定化合物的结构。结果分离得到4种甾体皂苷类化合物,其化学结构分别鉴定为:薯蓣皂苷(Ⅰ),纤细薯蓣皂苷(Ⅱ),26-O-β-D-吡喃葡萄糖基25(R)-22-羟基-呋甾-△⁵⁽⁶⁾-烯- 3β,26-二羟基-3-O-{[α-L-吡喃鼠李糖基(1→2)]-α-L-吡喃鼠李糖基(1→4)}-β-D-吡喃葡萄糖苷(Ⅲ),26-O-β-D-吡喃葡萄糖基25(R)-22-羟基-呋甾-△⁵⁽⁶⁾-烯-3β,26-二羟基-3-O-{[α-L-吡喃鼠李糖基(1→2)]-β-D-吡喃葡萄糖基(1→3)}-β-D-吡喃葡萄糖苷(Ⅳ)。结论化合物Ⅲ,Ⅳ为首次从穿龙薯蓣中分离得到的呋喃甾烷型皂苷。     

预知子药材HPLC-ELSD指纹图谱研究

目的: 建立不同产地预知子药材的HPLC-ELSD指纹图谱分析方法,并与不同产地预知子药材指纹特征相比较,为科学评价与有效控制预知子药材质量提供新方法。 方法: 采用HPLC-ELSD法测定了10个不同产地的预知子药材样品。使用Cosmosil-C₁₈色谱柱(4.6 mm×250 mm,5 μm),ELSD检测器,流动相乙腈-0.2%甲酸水,梯度洗脱,流速1.0 mL·min^-1,ELSD检测器,漂移管温度110℃,气流流速3.0 L·min^-1。采用直观分析和相似度软件评价不同产地预知子药材指纹图谱的相似度。 结果: 建立了不同产地预知子的HPLC-ELSD指纹图谱,检测了10个产地的预知子药材,标定了14个共有峰,各色谱峰分离度较好,相似度较高,达到了中药指纹图谱研究的技术要求。对其中的常春藤皂苷元3-O-β-D-吡喃葡萄糖基-(1→3)-α-L-吡喃鼠李糖基-(1→2)-α-L-吡喃阿拉伯糖苷(皂苷X,saponins X),常春藤皂苷元3-O-β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖苷(皂苷 B,saponins B),常春藤皂苷元3-O-α-L-吡喃鼠李糖基-(1→2)-α-L-吡喃阿拉伯糖苷(皂苷P_D,saponins P_D),常春藤皂苷元 3-O-α-L-吡喃阿拉伯糖苷(皂苷A,saponins A)进行了首次归属。 结论: 该法具有良好的重复性和稳定性,数据准确可靠,建立的HPLC-ELSD指纹图谱可为预知子药材的质量控制提供科学准确的依据。     

蒙药玉簪花中的甾体化合物

 目的 研究玉簪［Hosta plantaginea （Lam.）Aschers］花的化学成分。方法 利用溶剂法进行提取和萃取分部,采用硅胶柱色谱、Sephadex LH-20柱色谱进行分离,利用理化鉴别及现代波谱分析技术鉴定化合物的结构。结果 从中分离鉴定了6个甾体化合物,分别为(25R)-5α-螺旋甾烷-2α,3β-二醇（支脱皂苷元）（1）, (25R)- 2α,3β-二醇-5α-螺旋甾烷-12-酮（曼诺皂苷元）（2）,胡萝卜苷（3）,支脱皂苷元-3-O-{O-β-D-吡喃葡萄糖基(1→2)-O-β-D-吡喃葡萄糖基-(1→4)-β-D-吡喃半乳糖苷}（4）,支脱皂苷元-3-O-{O-β-D-吡喃葡萄糖基(1→2)-O-［β-D-吡喃木糖基(1→3)］-O-β-D-吡喃葡萄糖基-(1→4)-β-D-吡喃半乳糖苷}（5）和支脱皂苷元-3-O-{O-β-D-吡喃葡萄糖基-(1→2)-O-［O-α-L-呋喃鼠李糖基-(1→4)-β-D-吡喃木糖基(1→3)］-O-β-D-吡喃葡萄糖-(1→4)-β-D-吡喃半乳糖苷}（6）。结论 6个化合物均为首次从该植物中得到。
     

葛枣猕猴桃叶化学成分的研究

 目的对葛枣猕猴桃[Actinidia polygama(Sieb. et Zucc.)Miq]叶的化学成分进行分离鉴定。方法利用多种色谱手段对化学成分分离纯化,利用ESI-MS、¹H-NMR、¹³C-NMR等光谱数据鉴定其结构。结果分离得到8个单体化合物,分别鉴定为:山柰酚(Ⅰ),胡萝卜苷(Ⅱ),伞形花内酯(Ⅲ),山柰酚-3-O-β-D-吡喃半乳糖苷(Ⅳ),异鼠李素-3-O-β-D-吡喃葡萄糖苷(Ⅴ),山柰酚-3-O-α-L-鼠李糖基-(1→6)-β-D-吡喃半乳糖苷(Ⅵ),芹菜素-6-C-葡萄糖基-8-C-木糖苷(Ⅶ),山柰酚-3-O-α-L-鼠李糖基-(1→3)-α-L-鼠李糖基-(1→6)-β-D-吡喃半乳糖苷(Ⅷ)。结论化合物Ⅰ-Ⅷ均是首次从该植物中得到。     

Triterpenoid saponins of Acanthopanax nipponicus leaves

Five new triterpenoid saponins, nipponosides A-E (1, 3-6), were isolated from Acanthopanax nipponicus leaves, along with a known saponin, kalopanaxsaponin G (2). Nipponosides A-E were characterized as the 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester of 3-oxohederagenin, oleanolic acid 3-O-beta-D-glucopyranoside, gypsogenin 3-O-beta-D-glucopyranoside, 3beta,23,29-trihydroxyolean-12-en-28-oic acid, and 3beta,20alpha, 23-trihydroxy-30-nor-olean-12-en-28-oic acid, respectively. The structures of these new compounds were based on chemical and spectral methods.     

Five new triterpene saponins from Pulsatilla patens var. multifida

Five new oleanane-type glycosides (1-5), along with two known triterpene saponins, were isolated from the roots of Pulsatilla patens var. multifida (Ranunculaceae). The structures of the new triterpene saponins were elucidated as 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (1), hederagenin 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranoside (2), 3-O-beta-D-glucopyranosyl bayogenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (3), 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (4), and 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (5). Structure elucidation was accomplished by 1D and 2D NMR (HMQC, HMBC, and ROESY) methods, FABMS, and hydrolysis.     

Chemical constituents of the aerial parts of Schnabelia tetradonta

A phytochemical study on the ethanol extract of the aerial parts of Schnabelia tetradonta led to the isolation of five new compounds, 1-5, together with seven known compounds. The structures of the new compounds were elucidated on the basis of spectral data interpretation as 2alpha,3alpha,23,29-tetrahydroxyolean-12-en-28-oic acid (1), 3-O-beta-d-glucuronopyranosyl-2beta,3beta,16beta-trihydroxy-28-norolean-12-en-15-on-23-oic acid (2), 21-O-beta-d-glucopyranosyl-3beta,21alpha,30-trihydroxyolean-13(18)-en-24-oic acid (3), 6-C-beta-l-arabinopyranosyl-8-C-alpha-l-arabinopyranosylapigenin (4), and 4-acetylaminoethylphenyl 1-O-[6-O-(Z)-p-methoxycinnamoyl-beta-d-glucopyranosyl(1-->2)]-[beta-d-glucopyranosyl(1-->3)]-alpha-l-rhamnopyranoside (5), respectively.     

Flavanone glycosides from Miconia trailii

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia trailii yielded two new flavanone glycosides, matteucinol 7-O-alpha-l-arabinopyranosyl(1-->6)-beta-d-glucopyranoside (miconioside A, 1) and farrerol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (miconioside B, 2), along with the known compounds matteucinol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (3), matteucinol (4), 2alpha,3beta,19alpha-trihydroxyolean-12-ene-24,28-dioic acid (bartogenic acid, 5), 2alpha,3beta,23-trihydroxyolean-12-ene-28-oic acid (arjunolic acid, 6), 2alpha,3alpha,19alpha, 23-tetrahydroxyurs-12-ene-28-oic acid (myrianthic acid, 7), and stigmast-4-ene-3,6-dione (8). The structures of 1-8 were elucidated by spectroscopic methods, including 2D NMR.     

积雪草化学成分研究

目的：研究积雪草中的化学成分。方法：以硅胶、凝胶等多种柱色谱分离,制备高效液相色谱纯化,以波谱方法鉴定结构。结果：分离得到5个化合物,鉴定为阿魏酸二十二酯(1),bayogenin(2),3β-6β-23-trihydroxyolean-12-en-28-oic acid(3),3β-6β-23-trihydroxyurs-12-en-28-oic acid(4),D-gulonic acid(5)。结论：所有化合物均为首次从积雪草属植物中分离得到。     

Triterpenoid saponins from the roots of Pulsatilla koreana

Six new saponins, five lupanes (1-5) and one oleanane (6), along with 11 known saponins, were isolated from the roots of Pulsatilla koreana. The structures of the new saponins were found to be 23-hydroxy-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[O-beta-D-glucopyranosyl-(1-->4)]-alpha-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid (1), 23-hydroxy-3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid (2), 3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[O-beta-D-glucopyranosyl-(1-->4)]-alpha-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid (3), 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid (4), 23-hydroxy-3beta-[(O-beta-D-glucopyranosyl-(1-->4)-alpha-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid (5), and hederagenin 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside (6). Their structures were determined on the basis of 1D and 2D NMR ((13)C NMR, (1)H NMR, (1)H-(1)H COSY, HMQC, and HMBC) methods, FABMS, and hydrolysis. All isolated compounds were evaluated for their cytotoxic activity against A-549 human lung carcinoma cells.     

广西产美味猕猴桃根正丁醇部位化学成分研究

目的：研究广西产美味猕猴桃根正丁醇部位的化学成分。方法：应用色谱技术分离纯化，根据理化性质和波谱数据鉴定化合物结构。结果：从美味猕猴桃根正丁醇部位中分离并鉴定了6个化合物，分别为毛花猕猴桃酸B(1)，2α，3β，24 -三羟基-12-烯-28-乌苏酸(2)，2α，3α，24 -三羟基-12-烯-28-乌苏酸(3)，2α，3α，23-三羟基-12，20(30)-二烯-28-乌苏酸(4)，2α，3α，24-三羟基-12，20(30)-二烯-28-乌苏酸(5)，正丁基-O-β-D-吡喃果糖苷(6)。结论：化合物1～4，6均为首次从该植物中分离得到，其中化合物6为首次从猕猴桃属植物中分得。     

Tyrosinase inhibitory pentacyclic triterpenes and analgesic and spasmolytic activities of methanol extracts of Rhododendron collettianum

During the course of screening of medicinal plants of Pakistan for the isolation and structure elucidation of bioactive natural products, it was found that the methanol extract of the Rhododendron collettianum showed analgesic and spasmolytic activities. The methanol extract was then extracted with chloroform. Nine pentacyclic triterpenes were isolated from the chloroform extract and their structures were elucidated as erythrodiol (1), betulinic acid (2), maslinic acid (3), 2alpha,3alpha,23-trihydroxyolean-12-en-28-oic acid (4), bayogenin (5), arjunilic acid (6), methyl arjunolate (7), arjungenin (8) and 3beta, 23, 24-trihydroxyolean-12-en-28-oic acid (9). Among the triterpenes (1-9) tested, arjunilic acid (6) was found to be most potent. Their structure-activity relationship (SAR) showed that if the configuration of the -OH group at C-2 is changed from alpha to beta the potency is decreased. In most of the compounds the position and configuration of the -OH group was found to be important for the inhibitory potency against the enzyme tyrosinase. For the comparison, the standard tyrosinase inhibitors kojic acid (IC50=16.67 microm) and L-mimosine (IC50=3.68 microm) were used as controls.     

光叶珙桐化学成分的研究

目的:研究光叶珙桐 Davidia involucrata var.vilmoriniana 枝叶的化学成分。方法:采用薄层色谱,硅胶柱色谱,Sephadex LH-20凝胶柱色谱等方法进行分离纯化,使用波谱分析技术和理化常数对照等方法对得到的化合物进行结构鉴定。结果:从光叶珙桐的醋酸乙酯部位分离得到7个化合物,分别为没食子酸(3,4,5-trihydroxy-benzoic acid1),鞣花酸(ellagic acid2),顺丁烯二酸(maleic acid3),槲皮素(quercetin4),3-O-β-D-吡喃半乳糖基-槲皮素苷(quercetin-3-O-β-D-galactoside5),2α,3α,19α,23-tetrahydroxyurs-12-en-28-oic acid-28-O-β-D-glucopyranosylester(6),短叶苏木酚酸乙酯(ethyl brevifolin carbosylate7)。结论:化合物1~7均为首次从该植物中分离得到。