刺柳珊瑚Echinogorgia sp.中几个含氮化合物

从南海硇洲岛海域采集的刺柳珊瑚(Echinogorgia sp.)中分离到6个含氮化合物,经MS、NMR等光谱技术和比较文献,确定其结构分别鉴定为N-2-(1,3-二羟基-4,8-十八二烯基)-十六酰胺(1)、(E)-N-2-(1,3-二羟基-4-十八烯基)-十六酰胺(2)、尿嘧啶(3)、胸腺嘧啶脱氧核苷(4)、尿嘧啶脱氧核苷(5)、胸腺嘧啶(6)。这些化合物均为首次从该属柳珊瑚中的分离得到。     

钟花报春花的化学成分研究(Ⅱ)

从钟花报春花Primula sikkmensis Hook.中分离得到5个化合物,通过波谱分析其结构分别鉴定为5-羟基黄酮(1),2-苯基色原酮(2),5,8-二羟基黄酮(3),2’-羟基黄酮(4),3’-羟基-黄酮-4’-O-β-D-吡喃葡萄糖苷(5)。其中化合物1～4首次从该属植物中分离得到,化合物5首次从该植物中分离得到,并首次对3的NMR数据进行了归属。     

红波罗花的化学成分研究(英文)

从红波罗花(Incarvillea delavayi)植物的干燥全草乙醇提取物中分离得到12个化合物,通过MS和NMR等方法鉴定为tecomine(1)、epidihydrotecomanine(2)、2,6-二甲基-6-羟基-2-庚烯-4-酮(3)、marine B(4)、(3R,5S)-3-methyl-cyclopentyl[1,2-c]pyridine-5-ol(5)、3,4,5-三甲氧基苯甲酸乙酯(6)、cleroindicin B(7)、3,4,5-三甲氧基苯甲酸甲酯(8)、2-(4’-乙氧基苯基)-乙醇(9)、6-羟基苯并二氢呋喃(10)、β-谷甾酮(11)、β-乙酰齐墩果酸(12)。其中化合物1～3、5～6、8～12为首次从角蒿属植物中分离得到,所有化合物均为首次从该植物中分离得到。     

紫红獐牙菜中的酮类成分及其细胞毒活性

采用色谱分离手段对紫红獐牙菜Swertia punicea的乙醇提取物中乙酸乙酯和石油醚萃取部分进行分离纯化,运用1H NMR、13C NMR、HSQC、HMBC和ESI-MS等波谱方法和文献数据对比鉴定化合物结构,从紫红獐牙菜全草中得到8个口山酮类化合物,分别鉴定为1-羟基-2,3,5,7-四甲氧基口山酮(1)、1,2,3,4,5-五甲氧基口山酮(2)、1-羟基-2,3,4,7-四甲氧基口山酮(3)、1-羟基-2,3,5-三甲氧基口山酮(4)、dulcisxanthone C(5)、1-羟基-2,3,7-三甲氧基口山酮(6)、1,5-二羟基-2,3-二甲氧基口山酮(7)、1-羟基-3,4,5-三甲氧基口山酮(8),所有化合物均为首次从该植物中分离得到,化合物1、4、5、7对Hep G-2显现了很好的细胞毒活性。     

荔枝草抗氧化部位的化学成分研究

目的:研究荔枝草抗氧化部位的化学成分及单体化合物的抗氧化活性.方法:采用HP-20大孔树脂、硅胶、Sephadex LH-20及中压制备等手段,对荔枝草抗氧化部位进行分离纯化.根据理化性质和核磁、质谱数据解析化合物的结构;采用清除DPPH自由基和还原力实验测试总黄酮和单体化合物的抗氧化能力.结果:分离得到5个黄酮类化合物:楔叶泽兰素(1),高车前素(2),高车前苷(3),假荆芥属苷(4),5,7,4’-三羟基-6-甲氧基-二氢黄酮-7-O-β-D-葡萄糖苷(5)和2个苯丙素类化合物:咖啡酸(6)和迷迭香酸(7);抗氧化活性研究表明总黄酮和化合物均具有明显的抗氧化活性.结论:化合物5首次从野生荔枝草中分离得到,化合物7首次从该属分离得到;系统地分析了提取物和组分的抗氧化活性.     

欧洲李种子的化学成分研究

利用溶剂萃取和色谱分离手段,从蔷薇科植物欧洲李(Prunus domestica L.)种子中得到6个化合物。通过光谱分析,分别鉴定为松柏醛(1)、东莨菪亭(2)、(-)-二氢脱氢二松柏醇(3)、(-)-榕醛(4)、(E)-3,3’-二甲氧基-4,4’-二羟基茋(5)和5-羟甲基糠醛(6)。这些化合物均系首次从欧洲李种子中分离得到。     

木霉菌KK19L1发酵液中的一个新化合物

对菌株Trichoderma sp.KK19L1液体发酵,在该菌发酵液的乙酸乙酯层分离得到三个化合物,运用1H NMR、13C NMR和HR-ESI-MS等光谱学方法并参考相应的文献,确定其结构分别为(E)-3-acetylbenzyl but-2-enoate(1)、1-羟基-6-甲基-9,10-蒽醌(2)、2-甲基-3-羟甲基-5-羟基-7-甲氧基色原酮(3),其中化合物1为新的化合物,化合物3为首次在该菌株中分离得到。     

单叶蔓荆子黄酮类化学成分研究

采用MCI-Gel及硅胶等柱色谱法对云南西双版纳单叶蔓荆子的甲醇提取物的乙酸乙酯部分进行分离纯化,得到5个黄酮类似物,根据其理化性质,结合光谱技术(MS,NMR等)鉴定为紫花牡荆素(1)、3',5-二羟基-3,4',7-三甲氧基黄酮(2)、4',5-二羟基-3,6,7-三甲氧基黄酮(3)、牡荆葡基黄酮(4)和山奈酚-3-O-葡萄糖苷(5),化合物2～5为首次从该植物中分离得到.进行了抗羟基自由基氧化和抑菌活性的初步筛选实验,首次报道了化合物2、3的清除羟基自由基活性.     

中国被毛孢液体发酵的化学成分

本文采用反相硅胶、正相硅胶和Sephadex LH-20凝胶等层析技术对中国被毛孢液体发酵的化学成分进行研究。经1D-NMR(1H NMR、13C NMR、DEPT)、2D-NMR(HSQC、HMBC、1H,1H-COSY)和ESI-MS、HR-EI-MS解析鉴定,从其菌丝体中分离到腺苷(1)、2'-脱氧腺苷(2)、2,3-二羟基丙基壬烷酸酯(3)和4-羟基-6-戊基-四氢吡喃-2-酮(4),从发酵液中分离到4-甲基-1H-咪唑-5-乙醇(5)。化合物3和5首次以天然产物形式分离得到。     

滑桃树茎皮的化学成分

从大戟科植物滑桃树的茎皮中分离得到七个化合物,通过波谱分析或与已知化合物进行薄层层析对比,分别鉴定为β-谷甾醇(1)、胡萝卜甙(2)、蒲公英赛酮(3)、苔色酸乙酯(4)、苔色酸乙酯和甲酯混合物(4和5)、麦角甾-5α,8α-二环氧-22E,24R-6,22-二烯-3β-醇(6)和(2S,3S,4R,12E,2’R)-2-(2’-羟基-二十二碳酰胺基)二十碳-1,3,4-三羟基-12-烯(7)。其中化合物4、5、6和7为首次从该种植物中分离得到。     

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