Spectroscopic Studies on Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ) Complexes with 4,4'-Bipyridine

Fourier-transform infrared(FTIR),Raman and ultraviolet-visible spectra of 4,4'-bipyridine and its me-tal-organic coordination compounds synthesized from 4,4'-bipyridine and nitrate of Co(Ⅱ),Ni(Ⅱ) and Zn(Ⅱ) were measured and analyzed,respectively.The main FTIR and Raman bands were assigned in detail.The relationship between these characteristic bands and the structure of ligands and coordination compounds were discussed.     

含受电子生色基团烯类单体 - 对乙烯氧基甲基苯甲腈的合成及其荧光“结构自猝灭”效应

含受电子生色基团烯类单体 对乙烯氧基甲基苯甲腈的合成及其荧光“结构自猝灭”效应杜福胜李福绵（北京大学化学学院北京１００８７１）关键词对乙烯氧基甲基苯甲腈，吸收光谱，荧光光谱，“结构自猝灭”效应我们曾经报道过一系列含有给电子荧光生色基团的丙烯酰类及马...     

四(5,6-二氯-1,4-二硫杂环己烯)四氮杂卟啉及其锰(Ⅱ)、铁(Ⅱ)、镍(Ⅱ)、铜(Ⅱ)配合物的合成与性质

含硫四氮杂卟啉过渡金属配合物具有比金属卟啉、金属酞菁更为优异的光电功能和催化特性,故近十多年来颇受重视。我们对该类金属配合物和自由配体的合成、性质及其光-光、光-电转换,电化学、光电化学催化,光敏和气敏等功能正进行深入的研究。本文简要报道标题化合物的合成、表征和电子吸收光谱、发射光谱及顺磁共振波谱。     

Generation, isolation, and reactivity of a kinetically stabilized diphosphene anion radical

The stable lithium diphosphene anion radical, [Li(dme)₃]⁺[TbtPPTbt]⁻ (dme: 1,2-dimethoxyethane, Tbt: 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl), was readily synthesized by the one-electron reduction of the corresponding neutral diphosphene (TbtPPTbt). The molecular structure of the diphosphene anion radical was discussed in detail on the basis of its ESR, UV-Vis and Raman spectra, and theoretical calculations. The diphosphene anion radical was found to undergo ready chalcogenation reactions using elemental sulfur and selenium to afford the corresponding thiadiphosphirane and selenadiphosphirane, respectively.     

Structural and spectral studies of an iron(III) complex [Fe(Pranthas)2][FeCl4] derived from 2-acetylpyridine-N(4), N(4)-(butane-1, 4-diyl) thiosemicarbazone (HPranthas)

A novel iron(III) complex of 2-acetylpyridine N(4), N(4)-(butyl-1, 4-diyl) thiosemicarbazone (HPranthas), [Fe(Pranthas)₂]FeCl₄ was synthesized and physico-chemically characterized by means of partial elemental analysis, magnetic measurements (polycrystalline state), UV-Vis and IR spectroscopies. The presence of spin-paired iron(III) cation with ground state is revealed by the EPR and Mössbauer spectral data. Structure of the free ligand HPranthas and the complex [Fe(Pranthas)₂]FeCl₄ were solved by single crystal X-ray diffraction. The framework of iron(III) complex consists of a discrete monomeric cationic entity containing low spin iron(III) in a slightly distorted octahedral environment. The metal ion is bonded to one sulfur and two nitrogens of each thiosemicarbazone molecule. The tetrachloroferrate(III) ion acts as counterion.     

镧系间苯二甲酸配位聚合物的晶体结构及铕配合物的荧光特性

水热条件下合成了3个镧系间苯二甲酸的配位聚合物[Ln2(ip)3(H2O)2]n•n(H2O) (H2ip＝间苯二甲酸, Ln＝Pr (1), Eu (2), n＝0; Ln＝Ho (3), n＝1). 用X射线单晶衍射法测定了3个配合物的晶体结构, 它们皆属单斜晶系, 空间群P2(1)/n. 配合物1和2为双核单元的同构晶体, 两个独立的晶体学金属中心分别为七配位的五角双锥和八配位的二帽三角棱柱构型; 而配合物3略有不同, 金属离子分别处于七配位的单帽三角棱柱和八配位的扭变二帽三角棱柱构型中. 3个配合物中都存在由间苯二甲酸连接成的左旋和右旋的金属链构成的二维网状结构. 热分析结果表明, 3个配合物受热后分两步失去水分子, 再一步分解为Ln2O3. 配合物的荧光光谱表明, 铕配合物与其脱水产物均具有较强的荧光性质.     

胺类杂氮硅三环化合物红外光谱研究

对γ－氨丙基杂氮硅三环、γ－乙二胺基丙基杂氮硅三环、γ－乙二撑三胺基丙基杂氮硅三环３种化合物的红外光谱进行了研究。胺基的特征吸收为：伸缩振动ｖ_（ａｓ）（ＮＨ）和ｖ_ｓ（ＮＨ）；剪式振动δ（ＮＨ_２）。三环的特征吸收为：ＣＨ_２的弯曲振动ω（ＣＨ_２Ｎ）、ω（ＣＨ_２Ｏ）和τ（ＣＨ_２Ｏ）；Ｃ－Ｏ键的伸缩振动ｖ（Ｃ－Ｏ）；Ｎ－Ｃ键的伸缩振动ｖ_（ａｓ）（ＮＣ_３）和ｖ_ｓ（ＮＣ_３）；Ｓｉ－Ｏ键的伸缩振动ｖ_（ａｓ）（Ｓｉ－Ｏ）和ｖ_ｓ（Ｓｉ－Ｏ）；Ｃ－Ｃ键的伸缩振动ｖ（Ｃ－Ｃ）；以及Ｓｉ←Ｎ配键的伸缩振动ｖ（Ｓｉ←Ｎ）。     

水合铵硼氧酸盐及其饱和溶液的FTIR和Raman光谱研究

研究了NH₄B₅O₈·4H₂O和(NH₄)₂B₈O₁₃·6H₂O及其饱和溶液于20℃的FTIR和Raman光谱,对振动频率进行了归属.根据振动光谱特征,预测(NH₄)₂B₈O₁₃·6H₂O中所含基本结构单元为[B₇O ₁₁(OH)·B(OH)₃]^2-.首次将Raman光谱中516cm^-1处的强散射峰归属为这一多聚硼氧配阴离子的对称脉冲振动峰,并对以上2种铵硼氧酸盐饱和溶液中硼氧配阴离子的存在形式{B(OH)₃,[B₃O₃(OH)₄]^-和[B₅O₆(OH)₄]^-}和相互作用机理进行了探讨.     

蜂毒肽类似物的合成和生物活性研究

Melittin(GIGAVLKVLTTGLPALISWIKRKRQQ-NH₂)是蜂毒中含26个氨基酸残基的多肽,具有抗菌和溶血等生物活性,是典型的阳离子抗菌肽.本文设计合成了蜂毒肽C端15残基肽片段(GLPALISWIKRKRQQ-NH₂)及其类似物(15残基).研究了Melittin及这些合成肽的抗菌活性、溶血活性、疏水性及二级结构.结果表明,合成的类似物的溶血活性明显降低,抗菌活性基本保留,且与其疏水性相关.类似物中与碱性氨基酸簇(KRKR)距离较远的残基的疏水性对其抗菌活性有较大的贡献.多肽溶血与抗菌机理不同.类似物的抗菌活性和溶血活性与其二级结构(α-螺旋结构)没有明显的相关性.     

Simultaneous determination of 15 steroids in rat blood via gas chromatography-mass spectrometry to evaluate the impact of emasculation on adrenal

Adrenal was believed to affect the prostate tumor tissue growth by its secretion of adrenal androgens. However, the mechanisms regulating these effects were not fully understood. In this work, a sensitive and specific method for the determination of 15 steroids in blood via gas chromatography-mass spectrometry in selective ion storage detection mode was established to evaluate the impact of emasculation on adrenal steroids metabolism. Steroids were isolated by solid-phase extraction using Oasis HLB cartridge, and then derivated with heptafluorobutyric anhydride before analysis. The limits of detection were between 0.15 and 1.0 ng/mL and limits of quantification were between 0.62 and 2.6 ng/mL. The recoveries of steroids were above 83%, and both the intra-day and inter-day precisions (RSD%) were lower than 8%. Pregnenolone, progesterone, 17α-hydroxyprogesterone (17αP), 17α-hydroxypregnenolone (17αH), dehydroepiandrosterone (DHEA), estrone, 17β-estradiol, dihydrotestosterone (DHT), testosterone (T), 4-androstenedione (4-A), 1,4-androstadiene-3,17-dione, 11-deoxycortisol, 11-deoxycorticosterone, cortisol and aldosterone were quantified in 156 major male SD rats at 0, 1, 2, 4, 7 days, 2, 4, 6, 8, 10, 12, 14, and 16 weeks following emasculation. T and DHT decreased by 86.2% and 73.4%, respectively in the first 7 days following emasculation, but adrenal androgens (DHEA, 4-A) stabled at the normal level accordingly. Adrenal androgens and their precursors (17αH, 17αP) increased from the 2nd week along with the increase of androgens and the decrease of mineralocorticoids. These facts revealed that adrenal possibly enhanced its function of producing adrenal androgens from the 2nd week responding to the low androgens level induced by emasculation.     

荧光分光光度计的功能开发

固、液体吸收光谱测量的附件是由光阑、负透镜、全反射棱镜，吸收不也组成的光学系统，将它配置到进口荧光分光光度计上，可以扩展其功能，使其具有紫外分光光度计（ＵＶ）的功能，能够测量固体、液体样品的透射光谱和吸收光谱。     

Terahertz, infrared and Raman vibrational assignments of [FeFe]-hydrogenase model compounds

Using Raman, terahertz (THz), and mid-infrared (IR) spectroscopies, the vibrational spectra of two chromophore models of hydrogen-producing [FeFe]-hydrogenase, Fe₂(μ-S₂C₃H₆)(CO)₆ and Fe₂(μ-S₂C₂H₄)(CO)₆, have been assigned. The combination of absorption and scattering techniques, along with DFT calculations, allows for assignments to be made without traditional isotopic substitution methods.     

四（对—羟基）苯基卟啉配合物的傅里叶变换红外光声光谱

四（对-羟基）苯基卟啉（H2THPP）不仅能作为分析试剂，而且有一定的抗癌活性，还可作为合成卟啉类液晶材料的中间体．这种配体及其配合物由于颜色深、透光性能差和散射较强，用普通红外光谱法开展其振动光谱研究存在一定的困难．我们在用红外光声光谱（FTIR－PAS）技术[1]成功地研究了部分过渡金属、稀土金属叶琳配合物的基础上[2，3]，测试并研究了H2THPP及其Cr（III）、Mn（III）、Fe（III）、Co（II）、Ni（II）、Cu（II）、Zn（II）配合物在3700～200cm－1范围内的FTIR－PAS．对主要谱带进行了经验归属，讨论了配…     

Synthesis and Spectroscopic Properties of Acridinium-9-sulfonamides

By introducing an electro-withdrawing antipyrine group, N-(p-toluenesulfonyl)-N-(4-antipyrine)-10-methylacridinium-9-carboxamide triflate is prepared. The UV, fluorescent (FL), and chemiluminescent (CL) properties of the target compound and of its precursor are investigated by comparing with those of the model compounds N-(p-toluenesulfonyl)-N-phenyl-10-methylacridinium-9-carboxamide triflate and the corresponding precursor, respectively. The results show that, compared with the corresponding model compound, acridine sulfonamide with a heterocyclic antipyrine group exhibits blue shift of both UV absorption and of maximum excitation wavelength (λ_ex) and the emission wavelength (λ_em) in FL spectra. The λ_ex of the final target and its precursor are 268 and 274 nm, respectively, and the λ_em are 321 and 327 nm, respectively, whereas the λ_ex of the model compound and its unmethylated precursor are 365 and 359 nm, respectively, and the λ_em are 504 and 440 nm, respectively. Moreover, the chemiluminescence of the final target compound triggered by H₂O₂ could finish within 1.1 s, and the quantum yield is similar to that of the model compound, being 5.6 times high as that of luminol.     

Ground and low‐lying excited C2v states of FeO2—A challenge to computational methods

DFT (BPW91 and B3PW91), CCSD, CCSD(T), and MP2 geometry optimizations were performed on the lowest A₁, A₂, B₁, and B₂ singlet to septet states (a total of 16 states) of FeO₂, using in most cases the 6‐311+G(3df) basis set. With few exceptions, the different methods led to similar geometries. The lowest state is ³B₁ or ⁵B₂, depending on the method used. The quality of the various computational methods was tested by a comparison of vertical excitation energies with corresponding high‐level MRCI values. The best agreement with MRCI was found for BPW91 and B3PW91, with average deviations of about 0.2 eV. MRCI calculations were carried to extremely low configuration selection thresholds (0.025 μh) in order to find the lowest state of FeO₂. The full CI estimate (including Davidson correction and energy extrapolation to 0 μh) gave ³A₁ as the lowest state, followed by ⁵B₂ (0.03 eV) and ³B₁ (0.06 eV). Both ³B₁ and ³A₁ have geometries and vibrational frequencies consistent with the observed IR spectrum. The calculated adiabatic electron affinity of FeO₂ (from ³B₁ of FeO₂ to ⁴B₂ of FeO) is 2.46 eV with CCSD(T), and 2.22 eV with BPW91, compared with the experimental value of 2.36 eV. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009     

4-硝基咪唑A-带激发态结构动力学

通过共振拉曼光谱实验和量子化学计算的方法研究了4-硝基咪唑(4NI)A-带激发态衰变动力学.对4NI的振动光谱、紫外电子吸收光谱、荧光光谱和共振拉曼光谱进行了指认.在全活化空间自洽场法(CASSCF)/6-31G(d)计算水平下获得了单重激发态S1(nOπ*)和S2(ππ*)和势能面交叉点S1(nOπ*)/S2(ππ*)的优化几何结构和能量,分析了A-带共振拉曼光谱的强度模式特征,获得了短时结构动力学,并结合全活化空间自洽场法(CASSCF)理论计算结果确定了4NI在S2(ππ*)态衰变通道主要是S2,FC→S2,min(ππ*)→S0辐射弛豫.     

Bound Electron Enhanced Radiosensitisation of Nimorazole upon Charge Transfer

This novel work reports nimorazole (NIMO) radiosensitizer reduction upon electron transfer in collisions with neutral potassium (K) atoms in the lab frame energy range of 10–400 eV. The negative ions formed in this energy range were time-of-flight mass analyzed and branching ratios were obtained. Assignment of different anions showed that more than 80% was due to the formation of the non-dissociated parent anion NIMO^•− at 226 u and nitrogen dioxide anion NO₂⁻ at 46 u. The rich fragmentation pattern revealed that significant collision induced the decomposition of the 4-nitroimidazole ring, as well as other complex internal reactions within the temporary negative ion formed after electron transfer to neutral NIMO. Other fragment anions were only responsible for less than 20% of the total ion yield. Additional information on the electronic state spectroscopy of nimorazole was obtained by recording a K⁺ energy loss spectrum in the forward scattering direction (θ ≈ 0°), allowing us to determine the most accessible electronic states within the temporary negative ion. Quantum chemical calculations on the electronic structure of NIMO in the presence of a potassium atom were performed to help assign the most significant lowest unoccupied molecular orbitals participating in the collision process. Electron transfer was shown to be a relevant process for nimorazole radiosensitisation through efficient and prevalent non-dissociated parent anion formation.     

以卵磷脂为手性添加剂制备手性介孔二氧化硅

以十六烷基三甲基溴化铵(CTAB)的自组装体为模板,卵磷脂(PC)为手性添加剂,在n_PC:n_CTAB=1:21时,通过溶胶-凝胶法制备了螺旋介孔二氧化硅纳米棒。利用扫描电镜(FESEM)、透射电镜(TEM)、X-射线衍射以及氮气吸附-脱附等测试手段,对该纳米棒的形貌以及孔结构进行了表征。TEM显示该纳米棒的长度约为50~200nm,直径约为30~50nm。X-射线衍射表明孔道呈二维六方排列,虽然FESEM显示纳米棒左右手比例约为1:1,但通过圆二色谱表征证明该纳米棒在埃尺度下倾向于形成单一手性。结果表明,卵磷脂的手性可以传递到螺旋介孔二氧化硅纳米棒中。     

以卵磷脂为手性添加剂制备手性介孔二氧化硅

以十六烷基三甲基溴化铵(CTAB)的自组装体为模板,卵磷脂(PC)为手性添加剂,在n PC∶nCTAB=1∶21时,通过溶胶-凝胶法制备了螺旋介孔二氧化硅纳米棒。利用扫描电镜(FESEM)、透射电镜(TEM)、X-射线衍射以及氮气吸附-脱附等测试手段,对该纳米棒的形貌以及孔结构进行了表征。TEM显示该纳米棒的长度约为50～200 nm,直径约为30～50 nm。X-射线衍射表明孔道呈二维六方排列,虽然FESEM显示纳米棒左右手比例约为1∶1,但通过圆二色谱表征证明该纳米棒在埃尺度下倾向于形成单一手性。结果表明,卵磷脂的手性可以传递到螺旋介孔二氧化硅纳米棒中。     

Synthesis and Crystal Structure of a New Potassium Yttrium Diphosphate Dihydrate KYP_2O_7·2H_2O

The dihydrated potassium yttrium diphosphate=KYP2O7·2H2O=has been synthe- sized for the first time. Single-crystal XRD study has allowed the determination of its structure and correct formula. It crystallizes in the monoclinic system=space group P21/c=with the cell parameters a=7.7069(3)=b=10.5801(4)=c=10.0204(5)=β=93.24(3)°=V=815.76(6)3=Z=4=Mr=337.98=F(000)=656=Dc=2.752 g/cm3 and μ=8.073 mm-1. The single-crystal structure was solved from 1856 unique reflections with the final R=0.0365 and wR=0.0772=refined with 119 parameters. The atomic arrangement of KYP2O7·2H2O is built by the P2O7 groups=the YO7 and the KO10 polyhedrons which are connected by corner and edge-sharing to form a three- dimensional framework. Water molecules are directly bonded to the Y and K atoms=and they are located in channels running along the a direction.