印楝愈伤组织的化学成分

从印楝（Ａｚａｄｉｒａｃｈｔａ ｉｎｄｉｃａ Ａ．Ｊｕｓｓ）的愈伤组织中,共分离鉴定出５个化合物,经理化性质和波谱分析分别确定为：柳杉酚⑴,豆甾醇⑵,软酯酸－１－甘油酯⑶,豆甾醇－３－Ｏ－β－Ｄ－吡喃葡萄糖甙⑷,豆甾醇－３－Ｏ－β－Ｄ－吡喃葡萄糖甙－６’－十六烷酸酯⑸。     

大火草根部的化学成分

大火草（Ａｎｅｍｏｎｅ　ｔｏｍｅｎｔｏｓａａ（Ｍａｘｉｍ．）Ｐｅｉ）根状茎提取物的乙酸乙酯部分对粘虫（ＬｅｕｃａｎｉａｓｅｐａｒａｔａＷａｌｋｅｒ）有较好的非选择性拒食活性。从该部分分离得到１１个化合物,通过ＮＭＲ、ＭＳ等波谱分析确定它们的结构分别为４,５-二甲氧基-７-甲基香豆素（１）、４-甲氧基-５-甲基-６,７-二氧亚甲基香豆素（２）、４,７-二甲氧基-５-甲基香豆素（３）、齐墩果酸（４）、齐墩果酮酸（５）、齐墩果酸-３-Ｏ-β-Ｄ-吡喃木糖甙（６）、β-谷甾醇（７）、豆甾醇（８）、胡萝卜甙（９）、豆甾醇-３-Ｏ-β-Ｄ-吡喃葡萄糖甙（１０）和过氧化麦角甾醇（１１）。这些化学成分均为首次从该植物中分离得到,其中１和２为新化合物。     

牛至化学成分的研究

从药用植物牛至（Ｏｒｉｇａａｎｕｍ ｖｕｌｇａｒｅ Ｌ．）中分离并鉴定了８个化合物;乌素酸（１）、齐墩果酸（２）、原儿茶酸（３）、日本椴甙（４）、Ｓａｇｉｔｔａｔｏｓｉｄｅ Ａ（５）、胡萝卜甙（６）、β－谷甾醇（７）、豆甾醇（８）。２～５为首次从该种植物中分离得到。     

麻疯树根的化学成分研究

从麻疯树（Ｊａｔｒｏｐｈａ ｃｕｒｃａｓ Ｌ．）的根中分离到１３ 个化合物,经理化常数和波谱鉴定（ＩＲ、１Ｈ－ＮＭＲ、１３Ｃ－ＮＭＲ、ＥＩＭＳ和ＦＡＢＭＳ）分别为∶５α－豆甾烷－３,６－二酮（１）、川皮甙（２）、β－谷甾醇（３）、蒲公英脑（４）、２Ｓ－正二十四饱和脂肪酸甘油酯－１（５）、５－羟基－６,７－二甲氧基香豆素（６）、麻疯树酚酮Ａ（７）、麻疯树酚酮Ｂ（８）、６－甲氧基－７－羟基香豆素（９）、ｃａｎｉｏｊａｎｅ （１０）、３－羟基－４－甲氧基－苯甲醛（１１）、３－甲氧基－４－羟基苯甲酸（１２）和胡萝卜甙（１３）． 其中,化合物５ 为未见报道的新化合物,化合物１、２、９、１０、１１、１２ 为首次从该植物中分得,１０ 为含有过氧基团的二萜化合物． ７ 和８ 为一对四环二萜的立体异构体,并在碱中相互转化     

紫茎泽兰的化学成分

从紫茎泽兰（ＥｕｐａｔｏｒｉｕｍａｄｅｎｏｐｈｏｒｕｍＳｐｒｅｎｇ）中分离得到８个化合物,其中３－（２′－β－Ｏ－吡喃葡萄糖）－苯基－２－反式丙烯酸为一新化合物,其余为槲皮万寿菊素－７－β－Ｏ－葡萄糖甙,６－甲氧基山奈酚－７－甲基醚－３－β－Ｏ－吡喃葡萄糖甙,槲皮万寿菊素－４′－甲基醚－７－β－Ｏ－葡萄糖甙,６－羟基山奈酚－７－β－Ｏ－葡萄糖甙,６－甲氧基芜花素,伞形花内酯及正三十二醇。     

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     

赬桐的化学成分

应用正反相硅胶柱层析、中压柱层析、制备性薄层层析等手段,从桐（Ｃｌｅｒｏｄｅｎｄｒｕｍｊａｐｏｎｉｃｕｍ）中分离得到４个苯丙素甙类成分,根据光谱数据及化学方法,鉴定为马蒂罗甙（１）,单乙酰马蒂罗甙（２）,贞桐甙Ａ（４）以及阿克甙（３）,其中,贞桐甙Ａ是一新化合物。同时还得到２２,２３一二氢菠甾醇、豆甾醇、２５,２６一去氢豆甾醇,乌索酸,丁二酸酐和小麦黄素等。     

贞桐的化学成分

用正反相硅胶柱层析、中压柱层析、制备性薄层层析等手段,从贞桐中分离得到４个苯丙素甙类成分,根据光谱数据及化学方法,鉴定为马蒂罗甙（１）,单乙酰马蒂甙（２）,贞桐甙Ａ（４）以及阿克甙（３）,其中,贞桐甙Ａ是一新化合物。同时还得到２２,２３－二氢菠甾醇,豆甾醇,２５,２６－去氢豆甾醇,乌索酸,丁二酸酐和小麦黄素等。     

四川蜘蛛抱蛋的甾体皂甙

从四川蜘蛛抱蛋（Ａｓｐｉｄｉｓｔｒａ ｓｉｃｈｕａｎｅｎｓｉｓ Ｋ。Ｙ。Ｌａｎｇ ｅｔ Ｚ。Ｙ。Ｚｈｕ）根状茎中分离得到三个甾体皂甙,经光谱和化学方法分别鉴定为２２－甲氧基－５β－呋喃甾烷－１β,３β,４β,５β,２６－五羟基２６－Ｏ－β－Ｄ吡喃葡萄糖甙（１）,蜘蛛抱蛋皂甙（２）和原蜘蛛抱蛋皂甙（３）。（１）是一个呋喃甾醇型单糖链的新皂甙,（３）是本植物的主要皂甙。     

中药玄参的化学成分

从中药玄参（ＳｃｒｏｐｈｕｌａｒｉａｎｉｎｇｐｏｅｎｓｉｓＨｅｍｓｌ．）中分离得到１个新化合物：４－Ｏ－（对甲氧基肉桂酰基）－α－Ｌ－鼠李糖［４－Ｏ－（ｐ－ｍｅｔｈｏｘｙｃｉｎｎａｍｏｙｌ）－α－Ｌ－ｒｈａｍｎｏｐｙｒａｎｏｓｅ］;同时还分离到４个已知的环烯醚萜甙：爪钧草甙（ｈａｒｐａｇｉｄｅ）,爪钩草酯甙（ｈａｒｐａｇｏｓｉｄｅ）,Ｏ－甲基梓醇（Ｏ－ｍｅｔｈｙｌｃａｔａｌｐｏｌ）,士可玄参甙Ａ（ｓｃｒｏｐｏｌｉｏｓｉｄｅＡ）和１个已知的苯丙素甙：安格洛甙Ｃ（ａｎｇｏｒｏｓｉｄｅＣ）。新化合物的结构通过化学降解和光谱分析得到证明。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

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     

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.