小花清风藤的化学成分研究

利用Sephadex LH-20,硅胶柱色谱和硅胶制备薄层色谱等分离方法反复分离纯化,从小花清风藤（Sabia parviflora Wall．ex Roxb）中分离得到9个化合物,通过波谱数据分析分别鉴定它们为二十五烷酸（1）、木栓酮（2）、5-氧阿朴菲碱（3）、3-氧化齐墩果酸甲酯（4）、齐墩果酸（5）、羽扇豆-20（29）-烯-3-酮（6）、羽扇豆醇（7）、β-谷甾醇（8）、脱镁叶绿甲酯酸（9）。化合物2,6、7、9首次从该植物中分离得到。     

千金藤碱中的微量生物碱杂质

纯度达99.5%的千金藤碱经氧柱层析反复分离纯化,得到其中的微量杂质成分,通过波谱鉴定为（＋）-千金藤碱2＇-β-N-氧化物（1）.     

醉魂藤的化学成分研究

运用多种色谱技术从云南产醉魂藤Heterostemma alatum wight中分离得到10个化合物.通过理化鉴别和波谱数据确定了他们的化合物结构分别为β-谷甾醇(1)、正二十四烷酸(2)、芹菜素(3)、胡萝卜苷(4)、芹菜素-7-O-β-D-葡萄糖苷(5)、醉魂藤碱A(6)、醉魂藤碱B(7)、醉魂藤碱C(8)、醉魂藤碱D(9)和醉魂藤碱F(10).这些化合物均为首次从该植物中分离得到.     

小花清风藤叶的化学成分研究

对于小花清风藤的化学成分和药理作用的研究目前较少报道,为了阐明小花清风藤的物质基础,该研究对小花清风藤(Sabia parviflora)的干燥叶,采用反复硅胶柱色谱、Sephadex LH-20柱色谱、制备薄层色谱及重结晶等手段进行分离纯化,运用化学分析和波谱学方法鉴定化合物的结构。结果表明:从小花清风藤干燥叶的甲醇超声提取物中进行分离共得到12个化合物,分别为N-反式阿魏酰酪胺(1)、N-顺式阿魏酰酪胺(2)、N-反式-对-香豆酰酪胺(3)、N-顺式-对-香豆酰酪胺(4)、N-反式-对-香豆酰章鱼胺(5)、N-顺式-对-香豆酰章鱼胺(6)、阿魏酸(7)、芹菜素(8)、木犀草素(9)、咖啡酸(10)、5-氧阿朴菲碱(11)、齐墩果酸(12)。其中,化合物2、4-9为首次从清风藤属植物中分离得到,化合物1、3、10为首次从该植物中分离得到。     

百解藤的化学成分研究

从藤本植物百解藤(Cyclea polypetata)全株的乙醇提取物分离得到七个生物碱,根据理化性质和波谱特征,被鉴定为碱Ⅰ(Cycleanine)、碱Ⅱ(d-Tetrandrine)、减Ⅲ(Berbamine)、碱Ⅳ(d-lsochondodendrine)、碱Ⅴ(L-curine)、碱Ⅵ(Cycleanoline)和碱Ⅶ(Mag-nofloring).其中以L-curine为主碱,含量达0.8%,它是合成外科手术用药肌松剂氯甲左旋箭毒碱的原料.这一发现与前人报导颇有出入.这对开发利用我国新的箭毒植物资源具有重要意义.     

老瓜头中的化学成分

从老瓜头(Cynanchum komarovii Al.Iljinski)中分得10种化合物,根据理化常数、光谱分析及化学反应鉴定为7-脱甲氧娃儿藤碱(Ⅰ),表赤杨醇(Ⅱ),β-谷甾醇(Ⅲ),三十烷酸(Ⅳ),蔗糖(Ⅴ),氧化脱氧娃儿藤次碱(Ⅵ),磁麻脂(Ⅶ),牡丹酚(Ⅷ),β-谷甾醇-β-D-葡萄糖甙(Ⅸ)和葡萄糖(Ⅹ)。其中Ⅵ为微量新生物碱。生物试验结果表明,Ⅰ、Ⅵ及反应产物Ⅺ均具有细胞毒作用,后者亦为新化合物。     

鄂西清风藤化学成分及其α-葡萄糖苷酶抑制活性研究

为了研究鄂西清风藤在降低血糖方面的物质基础,该研究采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、半制备型高效液相色谱和重结晶等分离纯化方法从鄂西清风藤中提取分离化合物,并采用PNPG法筛选体外活性。结果表明:从鄂西清风藤95%乙醇提取物中分离得到10个单体化合物,分别为Pronuciferine (1)、(6R, 6aS, P)-Isocorydine (2)、N-methylhernovine (3)、N-formyldehydroanonain (4)、Roemerine(5)、(-)-Tetrahydropalmatine(6)、N-feruloyltyramine (7)、N-p-coumaroyltyramine (8)、Quercetin(9)、Dibutylphthalate(10)。所有化合物均为首次从该植物中分离得到。采用PNPG法筛选体外活性,研究结果显示化合物7、8、9具有明显的α-葡萄糖苷酶抑制活性,IC_(50)值为6.1～38.8μmol·L~(-1),其中化合物7、8的活性是阳性药阿卡波糖的40倍。该研究结果丰富了鄂西清风藤化学成分研究,为该植物在降血糖方面的开发提供了科学依据。     

盐地碱蓬的化学成分研究

采用硅胶、聚酰胺、Sephadex LH-20等色谱方法从盐地碱蓬乙醇提取液中分离得到6个化合物,分别鉴定为β-谷甾醇(1)、胡萝卜苷(2)、没食子酸(3)、槲皮素(4)、槲皮素-3-O--β-D-吡喃葡萄糖苷(5)和苯甲醇-β-D-吡喃糖苷(6).以上化合物均为首次从碱蓬属植物中分离得到.     

我国清风藤属药用植物研究概况

清风藤属(Sabia)植物是传统民间中药材,具有抗炎止痛、保肝、抗病毒等多种功效,因此具有重要的开发应用前景。通过查阅相关文献资料,从化学成分、临床药理作用、资源分布、生药鉴定、质量标准和提取工艺6个方面对该属植物的研究现状进行综述,为该属植物的进一步研究与开发提供参考。     

蝙蝠葛生物碱综合利用研究：Ⅱ.蝙蝠葛副碱的成份分离与鉴定

从蝙蝠葛中提取抗心律失常新药蝙蝠葛碱的同时可获得大量其他生物碱,该副碱具有多种重要生理活性,从中分离出二种生物碱,经化学和物理方法鉴定为蝙蝠葛苏林碱(daurisoline)和黄堇碱(corypalline),其中前者为副碱的主成分,后者为一首次从该植物中得到的简单异喹啉型生物碱。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various