变色马兜铃中银袋醌的分子结构研究

从变色马兜铃Ａｒｉｓｔｏｌｏｓｈｉａ ｖｅｒｓｉｃｏｌａｒ Ｓ．Ｍ．Ｈｗａｎｇ的根中分离到一个新的倍半萜醌,命名为银袋醌（Ｖｅｒｓｉｃｏｑｕｉｎｏｎｅ）,橙黄色短毛发状结晶,ｍｐ２９０－２９６℃（分解）,分子式Ｃ１５Ｈ１６Ｏ５,依靠１Ｈ－１３Ｃ ＮＭＲ ＣＯＬＯＣ谱和选择性远程ＤＥＰＴ谱,其分子结构补阐明为４,８－二羟基－３,６－二甲基－５－（２－羟基异丙基）－１,２－萘二酮。体外试验对人肝癌细胞     

工布乌头根中的二萜生物碱

工布乌头（ＡｃｏｎｉｔｕｍｋｏｎｇｂｏｅｎｓｅＬａｕｅｎｅｒ）系毛茛科乌头属植物,分布于西藏及四川西部,其块根有剧毒,泡酒外用可治疗跌打损伤和毒虫咬伤［１］。Ｙｕｅ等［２］、王锋鹏等［３］和庞志功等［４］曾从该植物分离到５个二萜生物碱。本文报道从四川产工布乌头的块根分离出的４个二萜生物碱。根据ＭＳ、１Ｈ－ＮＭＲ、１３Ｃ－ＮＭＲ等波谱分析,确定其中一个微量成分为新Ｃ１９－二萜生物碱,命名为工布生（ｋｏｎｇｂｏｅｎｓｉｎｅ,１）另外３个已知化合物分别鉴定为瓜叶乌碱甲素（２）、印乌碱（３）和它拉乌头胺…     

臭灵丹中四个新的倍半萜酸

从云南省芒市产臭灵丹［Ｌａｇｇｅｒａｐｔｅｒｏｄｎｔａ（ＤＣ．）Ｂｅｎｔｈ］中,分离得以４个新的桉烷型倍半萜酸,结构鉴定为５,１２－二烯－桉烷－１３－酸（１）;１β－式－５,１２－二烯－桉烷－１３－酸（２）;３β－羟基－５,１２－二烯－桉烷－１３－酸（３）。     

长果升麻的化学成分研究

从长果升麻（Ｓｏｕｌｉｅａ ｖａｇｉｎａｔａ）根茎中分离出６种皂甙,经光谱（ＦＡＢ－ＭＳ、１Ｈ－ＮＭＲ、１Ｈ－１Ｈ－ＣＯＳＹ、１３Ｃ－ＮＭＲ、１Ｈ－１３Ｃ－ＣＯＳＹ）分析,分别鉴定为２７－ｄｅｏｘｙａｃｔｅｉｎ（１）,ａｃｔｅｉｎ（２）,２５－０－乙酰升麻醇木糖甙（３）,２５－甲基升麻醇木糖甙（４）,升麻醇木糖甙（５）,２４－ａｃｅｔｙｌｈｙｄｒｏｓｈｅｎｇｍａｎｏｌ ｘｙｌｏｓｉｄｅ（６）,其中     

瓜叶乌头的二萜生物碱

从瓜叶乌头（ＡｃｏｎｉｔｕｍｈｅｍｓｌｅｙａｎｕｍＰｒｉｔｚ．）的块根分离到４个二萜生物碱,通过波谱分析和化学方法分别鉴定为８－ａｃｅｔｙｌ－１４－ｂｅｎｚｏｙｌ－ｅｚｏｃｈａｓｍａｎｉｎｅ（１）、ｃｈａｓｍａｎｉｎｅ（２）、ｉｎｄａｃｏｎｉｔｉｎｅ（３）和ｔａｌａｔｉｓａｍｉｎｅ（４）。其中１为新化合物,命名为瓜叶乌宁（ｈｅｍｓｌｅｙａｎｉｎｅ）。瓜叶乌宁（１）为白色块状结晶,ｍｐ１１５—１１６℃,［α］２０Ｄ＋１９．０２°。由ＦＡＢ－ＭＳ和ＥＩ－ＭＳ得知,分子量为６１３,１３Ｃ－ＮＭＲ中３２…     

细锥香茶菜甲素的结构订正和丙素的化学结构

前已报道［１］从唇形科香茶菜属植物细锥香茶菜（Ｒａｂｄｏｓｉａｃｏｅｔｓａ（Ｂｕｃｈ．Ｈａｎ．ｅｘＤ．Ｄｏｎ）Ｈａｒａ）中分离到３个结晶单体,并测定了其中两个单体——细锥香茶菜甲素（１）和乙素的结构。本文通过１Ｈ－１ＨＣＯＳＹ、１３Ｃ－１ＨＣＯＳＹ和ＮＯＥＳＹ,修订细锥香茶菜甲素（１）的结构为（２）,并经理化常数测定和光谱分析,确定了另一结晶单体——微量新成分细锥香茶菜丙素（３）的结构。（２）Ｒ１＝Ｒ２＝Ｒ４＝Ｈ,Ｒ３＝ＯＡｃ,Ｒ５＝ＯＣＨ３（３）Ｒ１＝Ｒ３＝Ｒ４＝Ｈ,Ｒ２＝ＯＡｃ,Ｒ５＝ＯＣＨ…     

毛叶香茶菜素的结构订正

我们从安徽省黄山产的大萼香茶菜（Ｒａｂｄｏｓｉａｍａｃｒｏｃａｌｙｘ（Ｄｕｎｎ）Ｈａｒａ）中分得一结晶,其元素分析和１３Ｃ－ＮＭＲ与毛叶香茶菜素［１］完全一致,故推定为毛叶香茶菜素,根据该结晶的元素分析,ＭＳ、ＮＭＲ、ＣＯＳＹ和ＮＯＥＳＹ等光谱数据,其结构应订正为（２）。表１表明：毛叶香茶菜素（２）的分子式由元素分析和高分辨质谱确定为Ｃ２４Ｈ３６Ｏ９,毛叶香茶菜素（１）的分子式由元素分析也应确定为Ｃ２４Ｈ３６Ｏ９。由于赵治清等误将质谱中Ｍ＋－Ｈ２Ｏ碎片离子峰ｍ／ｚ４５０当作分子离子峰（毛叶香茶菜…     

显示基因表达差异的PAGE—银染技术

ｄｄＲＴ－ＰＣＲ（ｄｉｆｆｅｒｅｎｔｉａｌｄｉｓｐｌａｙ　ｒｅｖｅｒｓｅｔｒａｎ－ｓｃｒｉｐｔｉｏｎ－ｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｏｎ）技术是Ｌｉａｎｇ和Ｐａｎｄｅｅ~（［１］）于１９９２年首先建立的一种在ＲＮＡ水平上显示基因表达差异,进而分离目的基因的有效方法。与其它分离基因的方法相比,ｄｄＲＴ－ＰＣＲ方法具有许多优点~（［２］）,目前已经成为筛选未知差异表达基因的最为有效的方法之一。ｄｄＲＴ－ＰＣＲ是３种技术的有机结合：（１）通过错定引物Ｔ１２ＭＮ（Ｍ＝Ａ、Ｔ、Ｃ、Ｇ,Ｎ＝Ａ、Ｃ…     

云南含笑中的新倍半萜醇

从云南含笑ＭｉｃｈｅｌｉａｙｕｎｎａｎｅｎｓｉｓＦｒ．ｅｘＦｉｎ．ｅｔＧａｇｎ中分离得到１个新的倍半萜醇,命名为１２,１３－ｄｉ－ａｃｅｔｏｘｙｌ－１．４．６１１－ｅｕｄｅｓｍａｎｅｔｅｔｏｌ,以及３个已知的倍半萜内酯１β－ｈｙｄｒｏｘｙａｒｂｕｓｃｕｌｉｎＡ２,ｒｅｙｎｏｓｉｎ３,ｐａｒｔｈｅｎｏｌｉｄｅ４和３个木脂素３－（α,４－ｄｉｈｙｄｒｏｘｙ－３－ｍｅｔｈｏｘｙｂｅｎｚｙｌ）－４－（４－     

短杆菌肽S与脂膜结合前后的H／D交换动力学的研究

短杆菌肽Ｓ（ＧＳ）是一个十肽分子（环－（Ｌ－Ｖａｌ－Ｌ－Ｏｒｎ－Ｌ－Ｌｅｕ－Ｄ－Ｐｈｅ－Ｌ－Ｐｒｏ）２）,是由两个β转角和两个β片层结构所构成［１］。ＧＳ的功能是通过破坏葛兰氏阴性菌的膜结构来完成其抗菌活性。迄今为止,人们对ＧＳ与膜结合特点的研究结果还不一致。Ｄａｔｅｍａｎ等人利用２Ｈ－ＮＭＲ,３１Ｐ－ＮＭＲ和ＤＳＣ等技术研究了ＧＳ与ＤＰＰＣ多层脂膜的相互作用,指出肽仅仅作用于膜表面［２］;而Ｈｉｇａｓｈｉｊｉｍａ等［３］及张凤立等用２Ｄ－ＮＭＲ的研究结果［４］表明,ＧＳ的疏水部分应插入膜内。蛋白质及多肽的Ｈ／Ｄ交换动力学受其分子内氢键,分子空间结构的致密度及其周边环境如膜环境［５］的影响。我们利用衰减全反射红外光谱（ＡＴＲ－ＦＴＩＲ）对与脂膜结合前后的短杆菌肽Ｓ的Ｈ／Ｄ交换动力学进行了研究,实验结果提示ＧＳ插入了脂膜双层。     

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.     

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.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).