N-Acetyl-N-{2-[(Z)-2-chloro-3,3,3-trifluoroprop-1-enyl]phenyl}acetamide

The title compound, C13H11ClF3NO2, adopts a Z conformation. Halogen center dot center dot center dot oxygen interactions [Cl center dot center dot center dot O = 2.967 (3) angstrom] in the crystal packing lead to the formation of a dimer joined by two Cl center dot center dot center dot O bonds.

Self-Assembly of Hyperbranched Multiarmed PEG-PEI-PLys(Z) Copolymer into Micelles, Rings, and Vesicles

Self-assembling of synthesized novel biodegradable hyperbranched amphiphilic poly(ethylene glycol)-polyethylenimine-poly(epsilon-benzyloxycarbonyl-L-lysine) (PEG-PEI-PLys(Z)) in aqueous media is studied. In aqueous media. PLys(Z) is the hydrophobic segment, with PEG and PEI as the hydrophilic segments. It will self-assemble into spherical shape when the selected solvent water is dropped into the common solvent tetrahydrofuran (THF). And when PEG-PEI-PLYS in common solvent is dropped into mixed solvent water and THF, rings will come into King. The spherical and rings are observed by environmental scanning electron microscopy (ESEM) and transmission electron microscopy ITEM). It shows that the size of the sphere is about 100 nm, and the diameter of ring distributes from 400 nm to 10 mu m and bigger with the time roll around.

Reversible B/Z-DNA transition under the low salt condition and non-B-form polydApolydT selectivity by a cubane-like europium-L-aspartic acid complex

We report here that a cubane-like europium-L-aspartic acid complex at physiological pH can discriminate between DNA structures as judged by the comparison of thermal denaturation, binding stoichiometry, temperature-dependent fluorescence enhancement, and circular dichroism and gel electrophoresis studies. This complex can selectively stabilize non-B-form DNA polydApolydT but destabilize polydGdCpolydGdC and polydAdTpolydAdT. Further studies show that this complex can convert B-form polydGdCpolydGdC to Z-form under the low salt condition at physiological temperature 37 degrees C, and the transition is reversible, similar to RNA polymerase, which turns unwound DNA into Z-DNA and converts it back to B-DNA after transcription. The potential uses of a left-handed helix-selective probe in biology are obvious. Z-DNA is a transient structure and does not exist as a stable feature of the double helix. Therefore, probing this transient structure with a metal-amino acid complex under the low salt condition at physiological temperature would provide insights into their transitions in vivo and are of great interest.

用Z-扫描技术研究手性介质非线性圆双折射

用Z 扫描技术研究了各向同性手性介质 (聚酯酰亚胺吡啶溶液 )对于左、右圆偏振光的非线性圆双折射 ,得到在低光强下非线性旋光角的变化规律 ,验证了非线性圆双折射与非线性旋光的关系。

镍催聚1,4-聚丁二烯橡胶的e_y,[Z]和f值与其内在的相关性

比较稀土催聚1，4—聚丁二烯橡胶和几种不同温度下聚合的镍催聚1，4—聚丁二烯橡胶的σｙ 和［η］，从中得知链缠结的变化是影响σｙ 和［η］以及 τ的主要原因，而微观结构的变化可能是影响链缠结的因素之一，1，4—聚丁二烯橡胶的加工性能与链缠结有关。

Synthesis, crystal structure and properties of (Z)-3-triphenylstannyl-1,1-diphenyl propenol

Five new organotin compounds were synthesized and characterized, X-ray crystal structure analysis of (Z)-3-triphenylstannyl-1,1-diphenyl propenol was performed, The crystal belongs to space group P2(1)/n. The cell parameters are: a = 1.235 7(2) nm, b = 0.987 4(2) nm, c = 2.208 1(4) nm, beta = 95.23(3)degrees, V = 2.683 0(9) nm(3), Z = 4, R = 0.027 9, R-w = 0.064 5. The tin atom of the molecule exists in a distorted tetrahedron, Z isomer of double bond is obtained.

(Z)-3-三苯基锡基-1,1-二苯基烯丙醇的合成、晶体结构和性质研究

合成并表征了５种新的有机锡化合物．测定了（Ｚ）－３－三苯基锡基－１，１－二苯基烯丙醇的晶体结构．晶体属于Ｐ２１／ｎ空间群，晶胞参数ａ＝１．２３５７（３）ｎｍ，ｂ＝０．９８７４（２）ｎｍ，ｃ＝２．２０８１（２）ｎｍ，β＝９５．２３（３）°，Ｚ＝４．分子结构是以锡为中心的畸变四面体构型，双键为顺式构型．并对其性质进行了研究.

(Z)-1[2-(苯基二溴化锡基)乙烯基]-1-环己醇的合成及晶体结构

报道了标题化合物〔C14H18Br2OSn〕的合成及晶体结构。该晶体属于单斜晶系，空间点群为P21/c，晶胞参数a=11.711(2)，b=9．114（2），c=16．864（3）A，β=102.94（1）°，V=1604.55（0）A3，Mr=480．78，Z=4，Dc=1．99g／cm3，u=65．20cm－1，F（000）=919，R=0．050，Rw=0．050．晶体结构由直接法解出。标题化合物分子中的锡原子被配体的2个碳、2个溴和1个氧原子配位，配位原子呈畸变的三角双锥构型，环已基为椅式构象，五员杂环为信封构象。

Crystal structure and mechanism of (Z)-1-[2-(phenyl-bromide-chloride)vinyl]-1-cyclohexanol

The crystal structure and mechanism of the title molecule are described. This crystal is orthorhombic, belonging to space group PC21/B with a=1,002 1(2) nm, b=1.483 0(3) nm, c=2.173 6(4) nm, V=3.230 39(2) nm(3), Z=2, D-c=1.80 g/cm(3), R=0.069 3. The structure was solved by direct method. The tin atom of the title compound exists in two distorted-trigonal-bipyramidal geometry, defined by two carbon, one bromide, one chloride and one oxygen atoms leading to a five-membered chelate ring. In the structure, the five-membered ring containing the intermolecular O-->Sn has a half chair conformation.

Synthesis and chemical properties of [Z]-1-[2-(triaryl stannyl)vinyl]cyclooctanol

The compounds of [Z]-1-[2-(triphenyl stannyl) vinyl] cyclooctanol (1) and [Z]-1-[2-(tri-p-tolyl stannyl) vinyl] cyclooctanol (2) were synthesized by the reactions of triphenyltin hydride and tri-p-tolyltin hydride with 1-ethynyl cyclooctanol. The crystal structure of compound 1 was determined. The reactions of compound 1 and 2 with IC1, Br-2, I-2 formed nine organotin halides. The organotin oxide or hydroxide were prepared by the reactions of [Z]-1-[2-(phenyl dibromo stannyl) vinyl] cyclooctanol (6) and [Z]-1-[2-(diphenyl monobromo stannyl) vinyl] cyclooctanol (5) with KOH. Three complexes were obtained by the reactions of [Z]-1-[2-(phenyl diiodide stannyl) vinyl] cyclooctanol (8) with three ligands (2,2'-bipyridyl,5-nitro-1,10-phenanthroline,8-Hydroxyquinoline). The sixteen new compounds synthesized in this paper were characterized by means of elemental analysis, IR, H-1 NMR. The reaction mechanism of triphenyltin hydride and tri-p-tolyltin hydride with 1-ethynyl cyclooctanol were also proposed.

[Z]-1-[2-(三芳基锡基)乙烯基]环辛醇的合成和性质

本文用三苯基氢化锡、三对甲苯基氢化锡作为锡氢化试剂与1-乙炔基环辛醇进行反应,合成了两个有机锡化合物:[Z]-1-[2-(三苯基锡基)乙烯基]环辛醇(1)和[Z]-1-[2-(三对甲苯基锡基)乙烯基]环辛醇(2),并测定了1的晶体结构.1和2分别与ICl,Br_2,I_2反应,得到六个有机锡一卤化物和三个有机锡二卤化物(3～11).有机锡二卤化物6和一卤化物5与KOH乙醇溶液反应,分别得到相应的锡氧化物和锡氢氧化物(12,13).有机锡二卤化物8分别与含氮双齿配体[2,2-联吡啶(Bipy),5-硝基-1,10-邻菲罗啉(Nphen),8-羟基喹啉(Oxin)]反应,得到三个相应的配合物(14～16).十六个新化合物通过元素分析、锡含量测定、IR、~1HNMR测定对其结构进行了表征,同时提出了1和2的生成反应历程.

高温高压下Z轴水晶的电导率实验研究

电导率测量的过程历经了从直流-交流-阻抗谱的过程，已经为地球物理学家借助于高温高压手段研究固体深部物质电学性质所广泛认同的。本文首先介绍了阻抗谱法测定水晶电导率的实验原理，进而采用该方法在10^-1～10^6Hz的频率范围以及1．0—4．0GPa和823—1073K条件下，借助于YJ-3000t紧装式六面顶高压设备对沿Z轴方向生长的水晶进行了的电导率实验就位测量。实验结果表明：在选择的频率范围，样品的复阻抗的模和相角都对频率具有很强的依赖性；随着温度的升高，电阻迅速降低，电阻率降低，电导率增大；在压力1．0—4．0GPa，其活化焓分别为：0．8548eV、0．8320eV、0．8172eV、0．7834eV，独立于温度的指前因子分别为：1．003S／m、1．778S／m、3．082S／m、6．987S／m，活化焓随着压力的升高而降低，指前因子随着压力的升高而增大。