蒙椴树皮化学成分的研究

为研究蒙椴（Tilia mongolica Maxim.）树皮的化学成分,通过溶剂萃取、硅胶柱色谱、重结晶分离纯化,从蒙椴树皮中分离得到7个化合物,根据其红外光谱、质谱和核磁共振谱数据鉴定为β-香树脂醇乙酸酯（1）,计曼尼醇乙酸酯（2）,羽扇豆醇（3）,二十四碳酸（4）,三棕榈酸甘油酯（5）,β-谷甾醇（6）,胡萝卜苷（7）。其中化合物1-5、7均为首次从椴树属植物中分离得到,化合物6为首次从该植物中分离得到。     

海南染木树茎的化学成分研究(Ⅰ)北大核心CSCD

研究海南染木树茎的化学成分,采用硅胶、Sehadex LH-20、ODS、HPLC等色谱技术对海南染木树茎乙醇提取物的乙酸乙酯部位进行分离和纯化,结合光谱数据和理化性质鉴定化合物的结构,分别为：4-甲基苯并喹啉-5,10-二酮（1）、白兰花碱（2）、鹅掌楸碱（3）、吲哚-3-甲醛（4）、羽扇豆醇（5）、霍烷-3,30-二醇（6）、熊果酸（7）、白桦酯酸（8）、30-羟基羽扇豆醇（9）、豆甾醇（10）、3β-乙酰基齐墩果醛（11）。其中,化合物4、7为首次从染木树属植物中分离得到,5、6、8、9-11为首次从该植物中分离得到。首次对化合物2的碳谱数据进行了归属。     

紫花苜蓿化学成分的研究(英文)

为研究紫花苜蓿（Medicago scttiva L．）地上部位的化学成分,通过溶剂萃取、硅胶柱色谱、凝胶柱色谱分离纯化,从紫花苜蓿地上部分分离得到9个化合物,根据质谱和核磁共振数据鉴定为小檗碱（1）、大黄素（2）、大黄素8-O-β-D-葡萄糖苷（3）、soyαsαpogenol B-3-O-β-glcA（4）、邻羟基苯甲酸（5）、反式对羟基肉挂酸（6）、顺式对羟基肉桂酸（7）、正三十烷醇（8）和β-胡萝卜苷（9）。其中化合物1—4为首次从苜蓿属植物中分离得到。     

新疆圆柏化学成分研究

从新疆圆柏枝叶中分离得到9个化合物,经理化性质和光谱解析分别为扁柏双黄酮（hinokiflavone,1）、芹菜甙元（apigenin,2）、鬼臼毒素（podophyllotoxin,3）、苦松甙（coniferin,4）、肉豆蔻酸丙酯（propionic acetate myristic acid,5）、β-谷甾醇（β-sitosterol,6）、圆柏醇（sabinal,7）、反式璎珞酸（trans-communic acid,8）、蔗糖（sucrose,9）,其中化合物1～4为首次从该植物中提取分离得到.     

刺玫果果肉石油醚层化学成分及胰脂酶和α-糖苷酶抑制活性研究北大核心CSCD

采用硅胶柱色谱、葡聚糖凝胶柱色谱等方法进行分离纯化,通过波谱数据进行结构鉴定,对石油醚层通过荧光检测法测定胰脂肪酶抑制活性,通过96微孔板法测定不同来源α-葡萄糖苷酶的抑制活性。从刺玫果果肉石油醚层分离得到12个化合物,分别鉴定为二十九烷（1）、α-生育酚（2）、邻苯二甲酸二乙酯（3）、邻苯二甲酸二丁酯（4）、β-谷甾醇（5）、α-香树脂醇（6）、乌苏醇（7）、白桦脂醇（8）、白桦脂酸（9）、19α-羟基乌苏酸（10）、胡萝卜苷（11）和麦芽糖（12）。化合物1~3、6~7和12首次从该植物中分离得到,石油醚层对胰脂肪酶和酵母菌来源的α-葡萄糖苷酶具有一定的抑制活性。     

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。     

地锦草脂溶性成分研究

采用硅胶柱层析的方法,从地锦草（Euphorbia humifusa Wild．）中分离得到5个化合物,经理化鉴别及波谱分析,鉴定为羽扇豆醇（1upeol,1）．cycloart-23E-en-3β,25-diol（2）．cycloart-23E-en-3β,25-diol（3）、cycloart-25-ene-3β,24-diol（4）、正十六碳酸α-甘油酯（1-glycerin hexadecylate,5）。化合物1～5均为首次从该植物中分离得到。     

白粉藤的木脂素和三萜成分

从白粉藤（Cissus repens Lank）地上部分分离得到5个木脂素和8个三萜,其中一个木脂素是新化合物,它的结构通过波谱分析和碱水解的方法鉴定为：（＋）-异落叶松树脂醇-9′-（2-对-香豆酰）-O-β-D-吡喃木糖苷（1）。其余化合物分别是：（＋）-异落叶松树脂醇-9′-O-β-D-吡喃木糖苷（2）,（＋）-Lyoniside（3）,（—）-开环异落叶松树脂醇-9-O-β-D-吡喃木糖苷（4）,（7′R,8′S）-4′-hydroxy-3′,5-dimethoxy-7,8′-dihydrobenzofuran-1-propanolneolignan-9′-O-β-D-xylopyranoside（5）,木栓酮（6）,表木栓醇（7）,蒲公英赛醇乙酸酯（8）,熊果酸（9）,2α-羟基乌索酸（10）,积雪草酸（11）,Niga-ichigoside F1（12）,羽扇豆醇（13）。这些化合物都是首次从该植物中分离得到。     

枸骨叶的化学成分研究

采用溶剂提取和柱层析色谱分离,根据化合物理化性质和光谱数据鉴定其结构.结果从枸骨叶中分离得到9个化合物,分别为羽扇豆醇(1)、3,28-乌苏酸二醇(2)、熊果酸(3)、异鼠李黄素(4)、山奈酚-3-O-β-D-葡萄糖苷(5)、地榆苷Ⅰ(6)、槲皮苷-3-O-β-D-葡萄糖苷(7)、异鼠李素-3-O-β-D-葡萄糖苷(8)、冬青苷Ⅱ(9).化合物7和8为首次从冬青属植物中分离得到,化合物5为首次从该植物中分离得到,同时首次报道了化合物9的13CNMR数据.     

臭牡丹全草化学成分的研究（一）

从臭牡丹全草的乙醇提取物的脂溶性部分分离得到三个单一尬发,经理化常数和波谱分析证明,化全物１为新化合物臭牡丹甾醇（ｂｕｎｇｅｓｔｅｒｏｌ）,化合物Ⅱ为桢桐酯（ｃｌｅｒｏｄｏｎｅ）,化合物Ⅲ为α－香树脂醇（α－ａｍｙｒｉｎ）,均为首次从该植物中得到。     

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     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV