肾茶化学成分的研究

从肾茶中分离得到11个已知化合物,通过NMR及MS数据分析,分别鉴定为：5-羟基-6,7,4’-三甲氧基黄酮（1）,5-羟基-6,7,3’,4＇-四甲氧基黄烷酮（2）,orthosipholF（3）,siphonolB（4）,白桦酯酸（5）,2α-羟基齐墩果酸（6）,2α,3α-二羟基-12-烯-28-齐墩果酸（7）,委陵菜酸（8）,蔷薇酸（9）,熊果酸（10）和胡萝卜甙（11）。其中,花合物2-9为首次从该植物中分离得到。     

干花豆中的三个异戊烯基黄烷酮

从滇产干花豆（Fordia cauliflora Hemsl.）茎的乙醇提取物中首次分离得到5个化合物,通过理化及波谱分析,它们分别确定为羽扇豆醇（1）、8,8-dimethyl-2-phenyl-10-prenyl-2,3-dihydro-8H-pyrano[3,2-g]chroman-4-one（2）、7-羟基-6,8-二异戊烯基黄烷酮（3）、7-甲氧基-8-异戊烯基黄烷酮（4）和齐墩果酸（5）.     

白木香内生真菌Botryosphae riarhodina A13固体发酵产物的分离鉴定北大核心CSCD

运用硅胶柱、反相硅胶柱、凝胶柱、HPLC和薄层制备等色谱技术及重结晶从白木香内生真菌Botryosphaeria rhodina A13的固体发酵产物中分离纯化了10个化学成分,通过化合物波谱数据及理化性质鉴定它们的结构分别为豆甾-4-烯-3-酮（1）、豆甾-5-烯-3β-醇-7-酮（2）、豆甾-4-烯-3,6-二酮（3）、（22E,24S）-5α,6α-环氧基-24-甲基胆甾-8（14）,22-二烯-3β,7α-二醇（4）、5,4＇-二羟-7-甲氧基黄酮（5）、香草酸（6）、对甲氧基苯甲酸（7）、尿嘧啶（8）、2-甲氧基对苯二酚（9）、2-甲基-3,5-羟基色酮（10）。其中化合物1～10均为首次从该属真菌中分离得到,化合物4具有细胞毒活性。     

龙血竭不同类型酚性成分的分离及紫外光谱特征

采用硅胶、反相硅胶、Toyopearl HW-40、Sephadex LH-20等柱层析以及高效液相色谱(HPLC)制备,从龙血竭的氯仿部分分离纯化得到22个化合物。经波谱分析鉴定为对羟基苯甲醛(1)、3,4,5-三甲氧基苯酚(2)、对羟基苯乙酮(3)、7,4’-二羟基黄烷(4)、(2S)-7,4’-二羟基8-甲基黄烷(5)、5,4’-二羟基7-甲氧基6-甲基黄烷(6)、(2S)-7,3’-二羟基4’-甲氧基黄烷(7)、7,4’-二羟基高异黄烷(8)、龙血素A(9)、龙血素B(10)、龙血素C(11)、2,4’-二羟基4-甲氧基二氢查耳酮(12)、4,4’-二羟基-2,6-二甲氧基二氢查耳酮(13)、6,4’-二羟基-2,4-二甲氧基二氢查耳酮(14)、剑叶龙血素D(15)、syringaresinol(16)、pinoresinol(17)、medioresinol(18)、(+)-lyoniresinol(19)、dihydrodehydrodiconifery alcohol(20)、3-methyl resveratrol(21)、紫檀芪(22)。其中化合物1~3、14、17~20为首次从云南龙血竭中得到。对其紫外特征光谱图分析发现:龙血竭中不同类型酚性成分紫外光谱特征有很大的差异,可用HPLC-DAD在线识别化合物的类型,指导酚性成分的分离纯化。     

岗松化学成分的研究

从岗松的石油醚和氯仿提取组分中分离得到7个化合物,根据NMR、HSQC、HMBC、IR和MS的数据分析及与文献对照,确定它们的结构为白桦脂酸(betulinic acid,1),齐墩果酸(oleanolic acid,2),没食子酸乙酯(ethyl sabre,3),5-羟基-6-甲基-7-甲氧基-二氢黄酮(5-hydroxy-6-methyl-7-methoxy-flavanone,4),5-羟基-7-甲氧基-8-甲基二氢黄酮(5-hydroxy-7-methoxy-8-methylflavanone,5),5-羟基-7-甲氧基-2-异丙基色原酮(5-hydroxy-7-methoxy-2-isopropylchromone,6)和β-谷甾醇(β-sitosterol,7).其中,化合物1～5和7为首次从该植物中分离得到.     

海南栽培肾茶的化学成分研究

为了解肾茶(Clerodendranthus spicatus)的化学成分,从海南栽培肾茶地上部分分离得到11个化合物,经波谱分析分别鉴定为:吐叶醇(1)、丁香脂素(2)、3,4-二羟基苯乙醇(3)、甜橙素(4)、5,6,7,4′-四甲氧基黄酮(5)、5-羟基-6,7,3′,4′-四甲氧基黄酮(6)、6-羟基-5,7,4′-三甲氧基黄酮(7)、5-羟基-6,7,3′,4′-四甲氧基黄烷酮(8)、3,3′,5-三羟基-4′,7-二甲氧基-二氢黄酮(9)、松脂素(10)和熊果酸(11)。化合物3、9和10为首次从肾茶中分离得到。对化合物1~6进行活性测试,结果表明化合物3~5对乙酰胆碱酯酶具有一定的抑制活性。     

晶帽石斛的化学成分研究

该研究利用硅胶、凝胶、MCI、中压制备色谱(MPLC)和高效液相半制备色谱(semi-HPLC)等方法,对晶帽石斛(Dendrobium crystallinum)进行了化学成分研究。结果表明:提纯、分离共得到10个化合物,经波谱数据分析及与文献数据对照,分别鉴定为石斛酚(1),3,4'-二羟基-5-甲氧基联苄(2),3,4',5-三羟基-3-甲氧基联苄(3),二氢藜芦醇(4),安告佛醇(5),3',5,7-三羟基-4'-甲氧基黄烷酮(6),4',5,7-三羟基-6-甲氧基黄烷酮(7),丁香树脂醇(8),β-谷甾醇(9),β-胡萝卜苷(10)。其中,除化合物2和化合物10以外,其余8个化合物均在该种植物中首次发现。     

长形肉豆蔻Myristica argentea Warb.化学成分研究(英文)

从长形肉豆蔻Myristica argentea乙醇提取物乙酸乙酯部分分离得到12个化合物,经理化和波谱分析分别鉴定为黄樟醚(1)、甲基丁香酚(2)、异甲基丁香酚(3)、3′-羟基异黄樟醚(4)、7-羟基-3′,4′-亚甲二氧基黄烷(5)、1,4-苯二甲酸二甲酯(6)、内消旋-二氢愈创木脂酸(7)、赤式-1-(4-羟基-3-甲氧基苯基)-4-(3,4-亚甲二氧基苯基)-2,3-二甲基丁烷(8)、赤式-1-(4-羟基-3-甲氧基苯基)-2-(2-甲氧基-4-(1(E)-丙烯基)苯氧基)-丙烷-1-醇(9)、nectandrin B(10)、β-谷甾醇(11)和胡萝卜苷(12)。化合物4~6和8~12为首次自该植物中分离得到,化合物4~6为首次从该属植物中分离得到。     

凹叶瑞香的化学成分研究(英文)

从凹叶瑞香的乙酸乙酯部位分离得到14个化合物,经理化性质及波谱数据分析分别鉴定为瑞香黄烷A(1),瑞香黄烷B(2),瑞香黄烷C(3),瑞香黄烷E(4),瑞香黄烷F(5),芫花素(6),芫根苷(7),4,′5-二羟基-3,′7-二甲氧基黄酮(8),瑞香新素(9),5′′-去甲氧基瑞香新素(10),左旋松脂酚(11),瑞香醇酮(12),紫丁香苷(13)和丁香醛(14)。化合物1～14均为首次从该植物中分离得到。     

镰形棘豆化学成分的研究

采用柱层析(CC)、短柱减压层析、重结晶等分离手段,从镰形棘豆乙醇提取液中分得7个已知化合物,经波谱分析鉴定为N-苯甲酰基-2-苯基乙胺(1),N-肉桂酰基-2-苯基-2-乙胺(2),N-苯甲酰基-2-羟基-2-苯基乙胺(3),2′-羟基-4′-甲氧基查儿酮(4),7-甲氧基黄烷酮(5)、5-羟基-7-甲氧基黄烷酮(6),β-谷甾醇(7).化合物1～3、5、6均为首次从该植物中分到.药理实验表明化合物4,5对人胃癌细胞株SGC有较强的细胞毒活性,IC50分别为3.61和6.11 μg/mL.     

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.     

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细