滇重楼地上部分的两个微量皂甙

从滇重楼地上部分中分离出两个新的微量的甾体皂甙ＰｏｌｙｐｈｙｌｌｏｓｉｄｅⅢ和Ⅳ,根据化学降解和光谱分析,它们的化学结构分别为２７－羟基－偏诺皂皂甙元－３－Ｏ［ａ－Ｌ－鼠李吡喃糖基（１→２）］［ａ－Ｌ－鼠李吡喃糖基（１→４－ａ－Ｌ鼠李吡喃糖基（１→４）］－β－Ｄ－葡萄吡喃糖甙,２３β,２７－二羟基－偏皂甙元－３－Ｏ－［ａ－鼠李吡喃糖（１→２）］     

鞭打绣球中的苯丙素甙和环烯醚萜甙

从鞭打绣球（ＨｅｍｉｐｈｒａｇｍａｈｅｔｅｒｏｐｈｙｌｌｕｍＷａｌｌ．）（玄参科）的全草中分离到２个新的苯丙素甙,命名为鞭打绣球甙Ａ和Ｂ（ｈｅｍｉｐｈｒｏｓｉｄｅＡａｎｄＢ）,２个已知的苯丙素甙,ｐｌａｎｔａｍａｊｏｓｉｄｅ和ｐｌａｎｔａｉｎｏｓｉｄｅＤ,以及３个已知的环烯醚萜甙,ｇｌｏｂｕｌａｒｉｃｉｓｉｎ,ｇｌｏｂｕｌａｒｉｎ和ｉｓｏ－ｓｃｒｏｐｈｕｌａｒｉｏｓｉｄｅ．通过化学和光谱分析,鞭打绣球甙Ａ和Ｂ的结构分别鉴定为２－（３－羟基－４－甲氧基苯基）乙基０－β－Ｄ－葡萄吡喃糖基（１→３）－４－Ｏ－反式阿魏醚基－β－Ｄ－葡萄吡喃糖试和２－（３,４－二羟基苯基）乙基Ｏ－［６－Ｏ－乙醚基－β－Ｄ－葡萄吡喃糖基（１→３）］－４－Ｏ－反式咖啡醚基－β－Ｄ－葡萄吡喃糖甙．     

滇重楼地上部分的配糖体

从滇重楼ＰａｒｉｓｐｏｌｙｐｈｙｌｌａＳｍ．ｖａｒ．ｙｕｎｎａｎｅｎｓｉｓ（Ｆｒ．）Ｈ－Ｍ,地上部分,分离出４个微量的配糖体,经光谱分析和化学降解证明其化学结构分别为２５Ｓ－异钮替皂甙元－３－Ｏ－α－Ｌ－鼠李吡喃糖基（１→２）［α－Ｌ－鼠李吡喃糖基（１→４）］－β－Ｄ－葡萄吡喃甙（Ａ）,２６－β－Ｄ－葡萄吡喃糖基－纽替皂甙元－３－Ｏ－α－Ｌ－鼠李吡喃糖基（１→２）［α－Ｌ－鼠李吡喃糖基（１→４）－β－Ｄ－葡萄吡喃糖甙（Ｂ）,山奈酚－３－Ｏ－β－Ｄ－葡萄吡喃糖基（１→６）－β－Ｄ－葡萄吡喃甙（Ｃ）,７－Ｏ－α－Ｌ－鼠李吡喃糖基－山奈酚－３－Ｏ－β－Ｄ－葡萄吡喃糖基（１→６）－β－Ｄ－葡萄糖甙（Ｄ）。     

仙茅根茎中的配糖体

从仙茅（ Ｃｕｒｃｕｌｉｇｏ ｏｒｃｈｉｏｉｄｅｓＧａｅｒｔｎ） 根茎中分离到７ 个化合物, 经光谱分析推定其化学结构分别为： ２, ６ － 二甲氧基苯甲酸（Ａ） ; 苔黑酚葡萄糖甙（Ｂ） ; 仙茅素Ａ （Ｃ） ; 仙茅甙（Ｄ） ; ２４ｓ, ３β, １１α, １６β, ２４ － 四羟基环阿尔廷醇－ ３ － Ｏ－ α－ Ｌ－ 鼠李吡喃糖基（１ →２） － β－Ｄ－ 葡萄吡喃糖甙（Ｅ） ; ２４ｓ, ３β, １１α, １６β, ２４ － 四羟基环阿尔廷醇－ ３－ Ｏ－ β－ Ｄ－ 葡萄吡喃糖基（１ →２） － β－ Ｄ－ 葡萄吡喃糖甙（Ｆ） 和胡萝卜甙（Ｇ） 。Ｆ为一新甙。     

石香薷中化学成分的研究

从石香薷（Ｍｏｓｌａ ｃｈｉｎｅｎｓｉｓ Ｍａｘｉｍ ．）中分离到１０ 个化合物,经光谱分析、化学方法及与已知化合物对照,分别鉴定为：６－甲基三十三烷（１）、β－谷甾醇（２）、熊果酸（３）、５－羟基－６,７－二甲氧基黄酮（４）、５－羟基－６－甲基－７－Ｏ－β－Ｄ－吡喃木糖（３→１）－β－Ｄ－吡喃木糖双氢黄酮甙（５）、５,７－二羟基－４－甲氧基黄酮（６）、洋芹素（７）、山奈素－３－Ｏ－β－Ｄ－葡萄糖甙（８）、桑色素－７－Ｏ－β－Ｄ－葡萄糖甙（９）、鼠李柠檬素－３－Ｏ－β－Ｄ－芹糖（１→５）芹糖－４－Ｏ－β－Ｄ－葡萄糖甙（１０）。其中,化合物５和１０ 为新化合物     

栓皮栎虫瘿的酚性成分及其生物活性

从栓皮栎（Quercus variabilisBl.）虫瘿中分离了２对平衡互变异构体和４个单体化合物,通过光谱数据和化学方法鉴定：Ｇ－１为１－Ｏ（３′－没食子酰基）没食子酰基－β－Ｄ－葡萄吡喃糖和１－Ｏ－（４′－没食子酰基）没食子酰基－β－Ｄ－葡萄吡喃糖的平衡互变异构体,Ｇ－２为３－Ｏ－没食子酰基－没食子酸和４－Ｏ－没食子酰基－－没食子酸的平衡互变异构体,-3O一１,６－二－Ｏ没食子酰基－β－Ｄ－葡萄吡喃糖,Ｇ－４为１,２,３,６－四－Ｏ－没食子酰基－β－Ｄ－葡萄吡喃糖,Ｇ－５为１－Ｏ－没食子酰基－β－Ｄ－葡萄吡喃糖,Ｇ－６为没食子酸甲酯。对Ｇ－１、Ｇ－３和Ｇ－４进行初步的抗肿瘤、抗脂质过氧化和抗血小板聚集活性实验。     

闭鞘姜根中的甾体皂甙

从闭鞘姜「Ｃｏｓｔｕｓ ｓｐｅｃｉｏｓｕｓ（Ｋｏｅｎｉｇ）Ｓｍｉｔｈ」根茎中分离出五个化合物。经波谱解析和化学降解,证明其化学结构分别为胡萝卜甙（Ａ）：薯芋皂甙元３－Ｏ－ａ－Ｌ鼠李吡喃糖基（１－２）－β－Ｄ－葡萄吡喃糖甙（Ｂ）;薯芋皂甙元３－Ｏ－ａ－Ｌ－鼠李吡喃糖基（１－２）「ａ－Ｌ－鼠李吡喃糖基（１－４）」β－Ｄ葡萄吡喃糖甙（Ｃ）;薯芋皂甙元－３－Ｏ－ａ－Ｌ－鼠李吡喃糖基（１－２）「β－Ｄ－葡萄     

滇黄芩甙A和B的结构

从龙胆科滇黄芩属植物滇黄芩(Veratrilla baillonii Franch)中分离得到两个新的酮二糖甙,经~1H NMR,~(13)C NMR,FAB-MS,MS,2D NMR,UV,IR等物理方法和化学反应,推定为:2,3,4,7-四甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(1)和7-羟基-2,3,4-三甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(2),分别命名为:滇黄芩甙A和滇黄芩甙B。     

滇黄芩中的两个山酮甙

从龙胆科滇黄芩属植物滇黄芩中分离得到两个新的山酮甙,分别命名为：滇黄芩甙Ｃ（Ⅰ）和滇黄芩甙Ｄ（Ⅱ）。     

蜘蛛抱蛋根茎中的甾体皂甙

从蜘蛛抱蛋（ＡｓｐｉｄｉｓｔｒａｅｌａｔｉｏｒＢｌ．）根茎的甲醇提取物中分离得两个甾体皂甙。经波谱解析及化学降解证明其化学结构分别为薯芋皂甙元一３一Ｏ－［Ｂ－Ｄ－葡萄吡喃糖基（１→２）］－［Ｂ－Ｄ－木吡喃糖基（１→３）］－Ｂ－Ｄ－葡萄吡喃糖基（１→４）－Ｂ－Ｄ一半乳吡喃糖甙（即蜘蛛抱蛋甙ａｓｐｉｄｉｓｔｒｉｎ）及新静诺特皂甙元－３－Ｏ－［Ｂ－Ｄ－葡萄吡喃糖基（１→２）］～［Ｂ－Ｄ－木吡喃糖基（１→３）－Ｂ－Ｄ－葡萄吡喃糖基（１→４）一Ｂ－Ｄ－半乳吡喃糖甙,后者为一新试,命名为新蜘蛛抱蛋甙ｒｅｏａｓｐｉｄｉｓｔｒｉｎ。     

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