1987年以来国外Ge-132生物学作用研究的新进展

综述了Ｇｅ－１３２的生物学作用研究的新进展。包括：１．免疫调节作用，可增强强的松增高血浆超氧化物清除活性，抗癌抗艾滋病活性，能有效地缓解晚期癌症疼痛。２。对＾６０Ｃｏ射白细胞生成超氧化物有保护作用，可刺激白细胞的Ｏ２＾－释放，防止＾６０Ｃｏ照射白细胞Ｏ２＾－生成减少，在高浓度时具有膜稳定作用。３．防止白内障的发生。４对抗白血病细胞的细胞毒作用，５．活化神经作用，有利于中风瘫患者的恢复。     

光电化学方法在铜缓蚀剂作用机理研究中的应用

本文综述了笔者实验室采用光电化学方法在铜缓蚀剂作用机理研究中的应用情况，采用此方法不仅可对铜缓蚀剂的缓蚀性能进行评定，而且还可对缓蚀剂的作用机理级缓蚀协同效应与作用机理进行研究，可以得到其它一些常规电化学方法及表面分析所不能得到的一些信息，此方法不失为一种研究缓蚀剂作用机进的好方法。     

硒对镉毒性的拮抗与解毒作用实验研究

不同剂量的硒对高剂量镉的拮抗作用引起大鼠全血中谷胱甘肽过氧化物酶活性和心肝、肾脏器相对重量的变化，用以评价硒对镉毒性的缓解作用，实验结果显示，经口给适量的硒对镉引起的毒性有拮抗作用，对机体有保护作用。     

钒胰岛素样作用研究进展

对钒酸盐的胰岛素作用的研究进行了综述，着重介绍了钒对糖尿病动物的降血糖作用及其机理的探讨。     

混合稀土化合物Y_（1－x）Tb_xCo_（5＋0．1x）的磁性

研究了白旋一轨道作用、晶场作用、交换作用、自旋一自旋偶极作用和Ｚｅｅｍａｎ作用，对稀土化合物Ｙ＿（ｌ－ｘ）ＴｂｘＣｏ＿（５＋０．１ｘ）的磁性实验数据进行了理论分析，理论计算结果与实验符合得较好，并进一步讨论了各种作用对磁性的贡献．     

A型流感病毒M2通道蛋白开闭机制：His37和Trp41间的氢键及阳离子-π作用的计算研究

A型流感病毒的M2蛋白为一四聚的离子通道．实验结果显示，通道的通透性可能与His37间的氢键网络，以及His37-Trp41间的阳离子-π作用网络有关．以4-甲基咪唑间的氢键网络模拟通道His37间的氢键作用，以质子化4-甲基咪唑和吲哚芳环体系来模拟His37和Trp41间的阳离子-π作用，用量子化学MP2／6—311G＊＊方法开展计算研究．结果显示，氢键网络中咪唑环间的每个N—H…N氢键作用强度可达-6．2kcal．mol^-1；阳离子-π作用网络中的每对阳离子．兀作用最高可达-18．8kcal．mol^-1（T-型作用构象）或-12．3kcal．mol^-1（平行堆积型）．因此，我们计算得到的作用能表明，通过pH调控氢键作用和阳离子-π作用网络进而调控M2通道的通透性是可能的．     

稀土化合物Ho2Co14Fe3的磁性分析

在分析稀土磁性常用的哈密顿中，引入了自旋－自旋偶极作用，用参数拟合的方法对Ｈｏ２Ｃｏ１４Ｆｅ３的磁化曲线进行了分析，计算结果与实验数据符合得很好，并且提示了Ｈｏ２Ｃｏ１４Ｆｅ３磁矩的突变现象。     

黄连抗菌作用的量热测定

黄连抗菌作用的量热测定孙海涛，刘永军，南照东，张洪林，袁久荣（曲阜师范大学化学系曲阜２７３１６５）（山东中医学院中药系济南）关键词黄连，抗菌作用，量热法一切生物活体在生长和代谢过程中都产生一定的热效应。近年人们已应用微量量热法测定了合成药物对细菌的抑...     

电磁波对化学反应非致热作用的实验研究

微波加快化学反应速度除微波对反应物的加热以外还有非致热的作用，本文用实验证实了电磁波对离子和极性分子的洛仑兹力的作用导致了指前因子和活化能的变化，并提出用电磁作用因子描术电磁波对化学反应作用的大小。     

混配配合物中配体间的疏水作用

混配配合物分子内配体间的疏水作用，为研究生物体内生理配体间的非共相互作用提供了一个极好的模拟。本文对混配配合物中配体间疏水为作用的涵义及其量度，研究的实验方法以及影响疏水作用的各种因素均作了详细的论述。     

互连式硼烷neo-B20H182-同分异构体的构型稳定性研究

富硼化合物的构型稳定性研究对其应用具有重要作用,通过设计9个独立的neo-B20H182-同分异构体,应用密度泛函方法G96PW91方法,结合SHC基组,对其几何结构进行优化,获得总能和电子性质,区分了它们的稳定性差异,并与分子前沿轨道能差得到的稳定性结论一致。其中(ae1,e1a)-C2h、(e12,e22)-D2、(e12,e2a)-C1、(a2,e2)-C2v和(e12,e22)-C2h等5个同分异构体稳定性相当,均属稳定分子构型;(e12,e1e2)-C1和(e12,ae1)-C1稳定性相当,为较稳定的同分异构体;(e12,e12)-C2h和(e12,e12)-C2v的总能和互连能都与前7个相差很大,属不稳定的同分异构体。论文还就影响互连键强度和分子稳定性的因素进行了讨论。     

Performance of W4 theory for spectroscopic constants and electrical properties of small molecules

Accurate spectroscopic constants and electrical properties of small molecules are determined by means of W4 and post-W4 theories. For a set of 28 first- and second-row diatomic molecules for which very accurate experimental spectroscopic constants are available, W4 theory affords near-spectroscopic or better predictions. Specifically, the root-mean-square deviations (RMSDs) from experiment are 0.04 pm for the equilibrium bond distances (r(e)), 1.03?cm(-1) for the harmonic frequencies (ω(e)), 0.20?cm(-1) for the first anharmonicity constants (ω(e)x(e)), 0.10?cm(-1) for the second anharmonicity constants (ω(e)y(e)), and 0.001?cm(-1) for the vibration-rotation coupling constants (α(e)). These RMSDs imply 95% confidence intervals of about 0.1 pm for r(e), 2.0?cm(-1) for ω(e), 0.4?cm(-1) for ω(e)x(e), and 0.2?cm(-1) for ω(e)y(e). We find that post-CCSD(T) contributions are essential to achieve such narrow confidence intervals for r(e) and ω(e), but have little effect on ω(e)x(e) and α(e), and virtually none on ω(e)y(e). Higher-order connected triples T(3)-(T) improve the agreement with experiment for the hydride systems, but their inclusion (in the absence of T(4)) tends to worsen the agreement with experiment for the nonhydride systems. Connected quadruple excitations T(4) have significant and systematic effects on r(e), ω(e), and ω(e)x(e), in particular they universally increase r(e) (by up to 0.5 pm), universally reduce ω(e) (by up to 32?cm(-1)), and universally increase ω(e)x(e) (by up to 1?cm(-1)). Connected quintuple excitations T(5) are spectroscopically significant for ω(e) of the nonhydride systems, affecting ω(e) by up to 4?cm(-1). Diagonal Born-Oppenheimer corrections have systematic and spectroscopically significant effects on r(e) and ω(e) of the hydride systems, universally increasing r(e) by 0.01-0.06 pm and decreasing ω(e) by 0.3-2.1?cm(-1). Obtaining r(e) and ω(e) of the pathologically multireference BN and BeO systems with near-spectroscopic accuracy requires large basis sets in the core-valence CCSD(T) step and augmented basis sets in the valence post-CCSD(T) steps in W4 theory. The triatomic molecules H(2)O, CO(2), and O(3) are also considered. The equilibrium geometries and harmonic frequencies (with the exception of the asymmetric stretch of O(3)) are obtained with near-spectroscopic accuracy at the W4 level. The asymmetric stretch of ozone represents a severe challenge to W4 theory, in particular the connected quadruple contribution converges very slowly with the basis set size. Finally, the importance of post-CCSD(T) correlation effects for electrical properties, namely, dipole moments (μ), polarizabilities (α), and first hyperpolarizabilities (β), is evaluated.     

Structural requirements in chiral diphosphine-rhodium complexes. VIII. Asymmetric hydrogenation of N-acetyldehydroamino acids with rhodium(I) complexes containing chiral carbocyclic analogues of DIOP.

Z--acetamidocinnamic acid was hydrogenated with neutral diphosphine-rhodium(I) complexes containing trans-1,2-bis(diphenylphosphinomethyl) cycloalkanes to give N-acetylphenylalanine: 86 % e.e.-(R) [(1R,2R)-cyclobutane]; 63 % e.e.-(R) [(1R,2R)-cyclopentane]; 35 % e.e.-(S) [(1S,2S)-cyclohexane]; and 82 % e.e.-(R) [(2R,3R)-DIOP]. Similarly, -acetamidoacrylic acid was hydrogenated to give N-acetylalanine: 72 % e.e.-(R) [(1R,2R)-cyclobutane]; 72 % e.e.-(R) [(1R,2R)-cyclopentane]; 40 % e.e.-(S) [(1S,2S)-cyclohexane]; and 73 % e.e.-(R) [(2R,3R)-DIOP].     

Raman spectrum investigation of the conformations of cis and trans methyl 1- hydroxy-3- methylcyclohexane-carboxylates

Summary The investigated cis and trans methyl 1-hydroxy-3-methylcyclohexanecarboxylates are mixtures of conversion isomers 1e3e1a3a and 1e3a1a3e with predominance in the first of the conformation 1e3e and in the second of 1e3a; moreover, in each of the two mixtures there is some admixture of the other. The Auwers-Skita is reversed for the compounds obtained.     

Theoretical study of electronic states of N22+in an intense radiation field

The Floquet states of N(2) (2+) created by the interactions of the six lowest singlet (1 (1)Sigma(g) (+), 1 (1)Delta(g), 2 (1)Sigma(g) (+), 1 (1)Pi(u), 1 (1)Pi(g), and 1 (1)Sigma(u) (-)) states of the dication with intense (0.4 x 10(13) Wcm(2)) radiation have been studied using the recently developed multireference configuration interaction method with single and double excitations (MRCISD)-based approach. The adiabatic Floquet state coinciding near its minimum with the initial X (1)Sigma(g) (+) ground state and asymptotically correlating with A (1)Pi(u) (m = -1), i.e., with one less photon in the dressed state, is expected to be metastable, as is the ground state in the absence of a field, but to support up to the v(max) = 12 quasibound vibrational level in comparison with v(max) = 11 in the parent field-free X (1)Sigma(g) (+) ground state. The tunneling lifetimes of the highest vibrational levels in this adiabatic Floquet state are predicted to be several orders longer than those in the parent field-free state. Analysis of the complete basis set limit extrapolated MRCISD potential energy curve of the field-free X (1)Sigma(g) (+) state of N(2) (2+) calculated in the present work (R(e) = 1.130 A, omega(e) = 2011 cm(-1), omega(e)x(e) = 26.1 cm(-1)) is in good agreement with spectroscopic experimental data. Calculations on the field-free A (1)Pi(u) state (T(e) = 12 106 cm(-1), R(e) = 1.252 A, omega(e) = 1438 cm(-1), omega(e)x(e) = 23.5 cm(-1)) generally support earlier theoretical work and do not support reported experimental values.     

分光光度法工作曲线不符线性关系的探讨 II: 关于在等色点波长测量

光度法工作曲线不成线性关系的情况多数是由体系存在逐级配合物所致, 为获得线性关系, 有人提出在两逐级配合物的主要等色点波长测量, 认为这样可以避免同时生成第二配合物的影响, 但没有深入的理论分析。本文通过实验与理论分析, 证明此法在多数情况下仅可改善线性关系, 但不能得到直线, 经进一步研究, 找到了这个问题的另外解决办法。     

Synthesis of nonaphenylenes and dodecaphenylenes using electron-transfer oxidation of Lipshutz cuprates and formation of nanostructural materials from hexadodecyloxynonaphenylene

Nonaphenylenes and dodecaphenylenes have been synthesized by using electron-transfer oxidation of Lipshutz cuprates with duroquinone. Oxidation of the Lipshutz cuprate derived from 4,4'-dibromo-o-terphenyl 3a in THF produced nonaphenylene 1a in 46% yield, whereas the similar oxidation of the Lipshutz cuprates derived from 4,4'-diiodo-4',5'-dialkyl-o-terphenyls 3b-d in ether afforded the corresponding nonaphenylenes 1b-d and dodecaphenylenes 2b-d in moderate total yields. In the case of 4,4'-diiodo-4',5'-didodecyloxy-o-terphenyl 3e as the starting material, oxidation of the corresponding Lipshutz cuprate in ether or THF only led to the formation of nonaphenylene 1e. Both nonaphenylenes 1a-e and dodecaphenylenes 2b-d are unreactive to light, atmospheric oxygen, and prolonged heating. These oligophenylenes showed strong UV absorption and fluorescent emission and exhibited some redox properties on CV analysis. Moreover, hexadodecyloxynonaphenylene 1e exhibits different nanostructures on the surface and in solution to form a film by casting a solution of 1e in cyclohexane, benzene, chloroform, THF, or diisopropyl ether (IPE) and nanofibers from IPE-MeOH (1:1), indicating different absorption and emission spectra and XRD patterns. The absorption maxima of THF solution, fiber, and film are in the order of 1e film (315 nm) > fiber (302 nm) > solution (295 nm), whereas the emission maxima are in the order of 1e fiber (425 m) > solution (418 nm) > film (401 nm). XRD analysis revealed that 1e aligns laterally on a glass or silicon surface to form a thin film with a lamella structure; however, it forms a nanofiber with a Lego-like stacking structure without pi-pi stacking interaction of the aromatic rings. Reflecting the different nanostructures of the 1e film and fiber, a spin-coated 1e film is found to be effective in detecting the vapor of explosives due to the intercalation of nitroaromatics to the cracked surface of the loosely stacked 1e. In contrast, the 1e fiber is not effective in detection of nitroaromatics but exhibits fluorescence anisotropy. The maximum fluorescence intensity is obtained in a direction perpendicular to the longitudinal axis of the fiber, indicating the stacking direction to be parallel to the longitudinal axis of the fiber.     

Experimental and theoretical studies of fused-ring persistent [1,2,4]thiadiazinyl radicals

Five persistent radicals 1a-1e were generated by the oxidation of 4H-[1,2,4]thiadiazines 2a-2e and studied with ESR and UV-vis spectroscopy. Three of the radicals, 1a, 1d, and 1e, were generated in high yields (>90%) using either SO(2)Cl(2)/amine in toluene or AgO/K(2)CO(3) in a toluene/MeCN mixture. Halogenated radicals 1d and 1e were sufficiently stable for chromatographic isolation and vacuum sublimation. The solution stability of the fluorinated 1d was measured at t(1/2) approximately 4 months in the absence of oxygen, and 1e at t(1/2) approximately 40 min in the presence of air. The crystal and molecular structures of 1d were determined by X-ray crystallography showing columns of parallel almost evenly spaced planar heterocycles connected by infinite ...N...S... chains. Cyclic voltammetry of 1d and 1e shows reversible reduction waves at about 0 V and irreversible oxidations at about 1.2 V. Spectral and electrochemical properties of 1 were well reproduced by DFT methods.     

Ab initio and DFT energetics of silylenic X–CNSi (X=H, F, Cl, and Br)

Singlet–triplet energy splitting for 24 silylenic reactive intermediates, X–CNSi (where X=H, F, Cl and Br), are compared and contrasted at 11 levels of theory: B1LYP/6-31++G**, B3LYP/6-31++G**, B1LYP/6-311++G**, B3LYP/6-311++G**, MP3/6-31G*, MP3/6-311++G**, MP2/6-31+G**, MP2/6-311++G**, MP4 (SDTQ)/6-311++G**, QCISD(T)/6-311++G** and CCSD(T)/6-311++G**. Each X-substituted silylenic species may either be singlet (s) or triplet (t), with one of the following three structures: 3-X-2-aza-1-silacyclopropenylidene (1_s-X, 1_t-X); [(X-imino)methylene]silylene (2_s-X, 2_t-X); and X-cyanosilylene (3_s-X, 3_t-X). For all X–CNSi species studied, orders of singlet–triplet energy separations (ΔE_s-t,X), appear as a function of electro-negativity (F>Cl>Br>H). For the six H–CNSi isomers (X=H), stability order is: 3_s-H>1_s-H>2_t-H>3_t-H>2_s-H>1_t-H. Likewise, stability order for the six isomers with X=F, is: 3_s-F>3_t-F>1_s-F>1_t-F>2_s-F>2_t-F. For X=Cl, the order of stability is: 3_s-Cl>1_s-Cl>3_t-Cl>2_t-Cl>1_t-Cl>2_t-Cl. Finally, the order of stability for six isomers of Br–CNSi is: 3_s-Br>3_t-Br>1_s-Br>2_s-Br>2_t-Br>1_t-Br. The lowest energy minimum, among all 24 species scrutinized, appears to be the singlet acyclic 3_s-X. Triplet silylene 2_t-H is suggested to be more stable than its corresponding 2_s-H at MP3, MP2 and DFT levels of theory. Comparisons between relative stabilities; multiplicities and geometrical parameters of 1–3 are discussed.     

Asymmetric Reduction of Aromatic Ketones and Asymmetric Hydroboration of 2-Phenyl-1-Alkenes with the Reagent Prepared from Borane-Methyl Sulfide and (15,25)-(+)-2-Amino-3-Methoxy-1-Phenyl-1-Propanol

Asymmetric reduction of aromatic ketones, with the reagent (1) prepared from borane-methyl sulfide (EMS) and (15, 25)-(+)-2-amino-3-methoxy-1-phenyl-1-propanol (3a) yielded the corresponding alcohols in 30–65% e.e. This reagent (1) is also effective for the asymmetric hydroboration of 2-phenyl-1-alkenes, isoelectronically similar to the aromatic ketones, and yielded the corresponding alcohols in 8–37% e.e.