中国番荔枝科植物抗癌有效成分研究

介绍了近年来我们实验室中国番荔枝科植物抗癌有效成分研究工作。从番荔枝科5种紫玉盘属植物,5种哥纳香属植物,1种番荔枝属植物,1种囊瓣木属植物中分离得到59种新的番荔枝内酯,32种新的多氧取代环己烯,12种新的苯乙烯吡喃酮和3种新的生物碱,并通过化学和光谱方法鉴定了它们的结构。大部分化合物显示了较强的抗癌活性。并对抗癌活性成分海南哥纳香醇甲进行了全合成。     

紫玉盘素B的分离与鉴定

从紫玉盘(Uvaria microcarpa)种子中首次分离得到二个白色蜡状固体, 经光谱分析鉴定: 一个为新的番荔枝内酯-紫玉盘素B(Microcarpacin B), 一个为已知的番荔枝内酯-Rollinicin。     

紫玉盘种子中的番荔枝内酯成分研究 Ⅰ.紫玉盘素(Microcarpacin)的分离及结构鉴定

从紫玉盘(Uvaria microcarpa Champ.ex Benth)种子中首次分离得到一个新的邻双四氢呋喃环番荔枝内酯(Annonaceous acetogenin)化合物—紫玉盘素(Microcarpacin).同时首次以纯化合物形式分离得到两个已知的番荔枝内酯NarumicinsⅠ和Narumicins Ⅱ.     

阿蒂莫耶番荔枝内酯的研究

本文首次报道从阿蒂莫耶番荔枝(Annona atemoya Hort)种子中分离到七个白色蜡状固体, 经光谱鉴定, 它们分别为已知的抗肿瘤活性番荔枝内酯(annonaceous acetogenin)-Asimicin, Motrilin, Isodesacetyluvaricin,Cherimolin-1, Almunequin, Squamocin-K和Neoannonin。     

N,N′-二苄基乙二胺类番荔枝内酯简化类似物的合成

运用生物电子等排原理及简化策略,设计含乙二胺结构片段的番荔枝内酯简化类似物.通过N,N′-二苄基乙二胺与两个手性环氧片段依次拼接,合成了手性简化类似物.其结构经1H NMR,13C NMR和MS表征.     

阿蒂莫耶化学成分的研究及阿蒂莫耶素B的分离和结构

从阿蒂莫耶(Annona atemoya Hort)种子中, 首次分离到四个白色蜡状固体,经光谱分析, 分别为新的番荔枝内酯(Annonaceous acetogenin)-阿蒂莫耶素B(Atemoyacin B)和三个已知的番荔枝内酯Bullatacin, Molvizarin和Rollinicin。     

番荔枝内酯————明日抗癌之星

本文介绍一类近年来被发现于番荔枝科(Annonaceae)植物中的强抗肿瘤活性化合物----番荔枝内酯(annonaceousacetogenin) , 从这类化合物的结构特点, 生理活性, 生源假说, 化学合成等几个方面综述了在该领域的氧基状况 .     

阿蒂莫耶素D的分离与结构

从阿蒂莫耶(Annonaatemoya(I)Hort)种子中分离到一个新的邻双四氢呋喃环型番荔枝内酯(Annonaceousacetogenin)-阿蒂莫耶素D(AtemoyacinD),同时分离到四个已知番荔枝内酯neo-annoninB、neodesacetyluvaricin、parviflorin和annonacin。     

番荔枝内酯的全合成研究进展

番荔枝内酯具有独特的化学结构和较强的抗肿瘤活性. 综述了近几年来这类天然产物的全合成研究进展.     

牛心果化学成分的研究

从牛心果(Annona glabra Linn)树皮中, 分离到三个白色蜡状固体, 经光谱分析, 它们分别为 强抗肿瘤活性番荔枝内酯(annonaceous acetogenin) 化合物-----annonacin,corossolone和solamin.     

环取代基对金属化聚苯胺衍生物膜修饰电极性能的影响

通过比较聚2，5－二甲氧基苯胺（PDMAn）、聚邻甲基苯胺（POT）和聚间氯苯胺（PmClAn）膜修饰电极的氧化还原电位、沉积在这3种聚合物上的铂微粒的表面形态与晶面取向以及异丙醇在分散Pt微粒的聚苯胺膜修饰电极上的氧化行为，从电子效应和立体效应探讨了聚合物电化学性质与环取代基的关系以及不同聚合基质对Pt沉积机理和有催化性能的影响,结果表明，在硫酸溶液中PDMAn膜修饰电极的氧化还原电位最负、POT次之、PmClAn最正，Pt在PDMAn和POT膜上的电沉积机理与在PmClAn膜上的不同，聚合物膜上沉积的Pt微粒呈现（200)晶面择优取向，其中POT膜上择优取向度最大，PDMAn次之，Pm-ClAn最小，异丙醇在金属化聚合物膜电极上的氧化电位取决于聚苯胺的本质，在POT膜修饰电极上异丙醇的电氧化主要发生在POT的活性电位区，而在PDMAn与PmClAn膜上的电氧化则主要发生在Pt上的氧化电位区，说明聚合物膜不仅作为Pt微粒的分散介质，而且本身有产生催化作用。     

核酸的有机化学研究在分子生物学发展中的作用

本文主要综述有机化学在建立核酸的顺序测定法和自动顺序仪,在破译遗传密码,在建立核酸片段的化学合成方法,固相合成法及DNA合成仪的设计,在合成许多有生物活力的核酸分子,在发展并完善遗传工程以及新近发现酶RNA(Ribozyme)等方面的卓越贡献。最后简要地展望有机化学将对生物学发展作出进一步贡献的几个方面。     

Growth and characterization of pyrene crystals on carbon nanofibers

Pyrene crystals were grown on carbon nanofibers (CNFs) by dispersing pyrene polycrystals and CNFs in water during ultrasonic irradiation, and they were characterized by scanning electron microscopy, X-ray diffractometry (XRD) and spectroscopy. The XRD measurements indicated that the orientation and size of the pyrene crystals on the CNF aggregates were different from that of the added pyrene polycrystals. Based on the spectroscopic properties of the pyrene crystals on the CNFs, the pyrene crystals on the CNF aggregates and on the individual CNFs were determined to be polycrystals and single crystals, respectively. These results indicate that pyrene crystals are produced on the CNFs by recrystallization of the added pyrene polycrystals and their crystal states depend on the aggregation state of the CNFs.     

Recent progress in experiments for sessile droplet wetting on structured surfaces

Wetting of a sessile droplet on structured or patterned surface can be found in a broad range of applications. The researchers have been promoted to keep working on the topic. The review is on the basis of the recent experimental advances on the sessile droplet wetting on the hydrophobic, hydrophilic, or combined hydrophobic and hydrophilic surfaces under isothermal conditions, and on heating or cooling substrates having nonisothermal conditions. More attention has been paid on the wetting configuration between the sessile droplet and the structured substrate; the research gap has been discussed on identifying the three-phase line shape. Further, the three-dimensional measurement for the sessile droplets on the patterned surfaces with focusing more on the contact line of sessile droplets might reveal new physical insights. This review targets at building a holistic overview on the sessile droplet wetting behaviors on the structured substrate in the past 2 years.     

含铈Cu-Fe-O催化剂的氧化还原性研究

用TPR等方法研究了Cu-Fe-Ce-O/γ-Al₂O₃(Ⅰ)催化剂的氧化还原性能。结果表明,在(Ⅰ)中铜的存在有利于Fe₂O₃的还原,铈作为助催化剂能增强Cu-Fe-O/γ-Al₂O₃(Ⅱ)的氧化还原性能,配合CO、NO和CO+NO气对试样进行预处理后发现,铜吸附CO的能力比铁强,铁吸附NO的能力比铜强,铈的存在可增强(Ⅱ)在NO+CO反应气氛中对CO的吸附能力,并对NO在催化剂表面吸附形成硝酸盐物种产生影响。     

Influence of coadsorbates on the NO dissociation on a rhodium(311) surface.

Density functional theory (DFT) studies were performed to investigate the influence of coadsorbates on the nitrogen oxide dissociation on the vicinal rhodium(311) surface. This study amplifies prior studies on the dissociation of oxygen and nitrogen oxide on the (111) facet of rhodium. The influence of coadsorbates on the kinetic parameters and thermochemistry of the NO dissociation on Rh311 was studied. In addition, the activation energy and thermochemistry of this reaction were determined as a function of oxygen preoccupation/initial coverage. Steric and electronic effects and their influence on the dissociation reaction were examined. The results are discussed in the face of an NOx dissociation catalyst system proposed by Nakatsuji.     

不同取代基的噻碳菁和吲哚碳菁染料对其在溴化银微晶上吸附能力及形成J-聚集体尺寸分布的影响

本文研究了5-位不同取代基的噻碳菁和吲哚碳菁染料对其在立方型颗粒和T-颗粒溴化银微晶上吸附能力的影响,并采用ACFEM(Analytical Color Fluore scence Electron Microscopy)研究了上述结构染料对其吸附在溴化银微晶所形成的J-聚集体尺寸分布的影响。实验结果表明,对吲哚碳菁染料来说,立方体溴化银微晶表面的吸附能力较T-颗粒溴化银微晶表面的吸附能力强;但对噻碳菁染料来说则相反,它们在T-颗粒溴化银微晶表面的吸附能力较立方体溴化银微晶表面的吸附能力强。另外,对5-位不同取代基的噻碳菁染料而言,无论是在立方型颗粒或T-颗粒溴化银微晶上的吸附能力来说,含取代基(无论4-取代基是吸电子型还是推电子型)的噻碳菁染料较未取代的噻碳菁染料强;而5-位取代基是吸电子型的噻碳菁染料更有利于其吸附在T-颗粒溴化银微晶表面。此外,本文还进一步证明了溴化银微晶表面上染料J-聚集体的生长过程是符合奥斯瓦尔特成熟过程的。吲哚碳菁染料在T-颗粒溴化银微晶上形成的J-聚集体的平均尺寸明显大于在立方体溴化银微晶上形成的J-聚集体的平均尺寸。吸附在立方体溴化银微晶上的5-不同取代基的噻碳菁染料对其形成J-聚集体尺寸分布的影响的研究结果表明,含取代基(-CH₃,-Ph,-Cl)的噻碳菁染料形成的J-聚集体的尺寸分布几乎相同,但与未取代的噻碳菁染料形成的J-聚集体的尺寸分布明显不同;5-位含取代基的噻碳菁染料形成的J-聚集体平均尺寸大于未取代的噻碳菁染料的。     

咪唑啉酰胺在电偶电极表面的吸附行为

采用原子力显微镜技术研究了有机阳离子缓蚀剂(咪唑啉酰胺)在电偶电极表面的吸附行为, 并探讨了其腐蚀抑制机理. 结果表明, 金属表面的过剩电荷较大地影响缓蚀剂分子的吸附行为. 在1%的NaCl溶液中, 碳钢电极表面带有过剩的负电荷；不锈钢电极表面带有过剩的正电荷；碳钢电极和不锈钢电极耦合后, 其表面分别带有过剩的正电荷和负电荷. 在耦合前阳离子缓蚀剂分子仅吸附在碳钢表面, 耦合后缓蚀剂分子在偶对的阴极(不锈钢)和阳极(碳钢)表面均有吸附, 但缓蚀剂分子在碳钢表面的吸附强度和覆盖度较之耦合前降低, 缓蚀剂的腐蚀抑制能力减弱.     

Influence of Mg^2＋ on Initial Stages of CaCO3 Scale Formed on Metal Surface

Magnesium ions, which exist in formation water and injection water under downhole conditions in the oil and gas production industry, are a key determinant in the CaCO3 scale formation. Many studies have focused their attention on the effect of magnesium on the kinetics, the morphology and the content of Mg in the Ca-CO3 scale. Little attention has been paid to the effect of Mg^2 on the initial stages of CaCO3 formation on a metal surface. In this study, an electrochemical technique was used to study the influence of Mg^2 on the ini-tial stages of CaCO3 scale formed on a metal surface. With this electrochemical technique, the reduction of the dissolved oxygen in an analysis solution is considered on the surface of a rotating disk electrode (RDE) un-der potentiostatic control. The rate of oxygen reduction on the surface of the RDE enables the extent of sur-face coverage of scale to be assessed. With this electrochemical technique, a new insight into the effect of Mg^2 on CaCO3 scale formed on a metal surface is given.     

Ru上有氧条件下氨分解的动力学研究

IthasbeenshownthatRuisvalidforthesyn thesisanddecompositionofammonia[1,2 ] .FurtherstudyofammoniaadsorptionanditsdecompositionproductsdesorptiononRuwillbeimportant .Previ ousstudiesofammoniaadsorptiononRumainlyfo cusedontheammoniasynthesisandhydrogenpro ductionintheabsenceofoxygen[3] ,onlyafewinves tigationsonammoniadecompositioninthepresenceofoxygenhavebeenreported[4 ,5] ,andtheeffectofad sorbedoxygenontheratesofammoniadecompositionandproductformationonRuarestillnotwellunder stood .Inthispa…