一种新型脑灌注显像剂99mTcN-CPDTC的制备及生物分布

目前临床上广泛使用的99mTc脑灌注显像剂是以［99mTcO］3+核为中心核的配合物99mTc-乙撑双半胱氨酸二乙酯(99mTc-ECD)和99mTc-六甲基丙撑二胺肟(99mTc-HMPAO). ［99mTc≡N］2+核由于具有较高的化学稳定性以及用99mTcN核代替99mTcO核后其配合物的生物分布性能发生了较大的改变［1～3］, 因此研究含99mTcN核的配合物成为寻找新型放射性药物的一条有效途径.     

CO2与HCN,NH3,H2O分子络合物的从头计算研究

用ab initio能量梯度法(3-21G基组)分别优化CO_2与HCN、NH_3、H_2O_3个分子络合物的平衡几何构型。结果表明HCN、NH_3和H_2O中的N或O原子与CO_2中的C原子之间形成较弱的范德华键,三者的范德华键键长分别为0.2865、0.2775、0.2543nm,稳定化能分别为14.8、27.0、31.2kJ·mol~(-1),3个分子络合物的构型都呈T型,对3个分子络合物的稳定化能的能量分解研究表明它们的形成主要靠静电作用能。     

用离散-连续模型计算NH2-,NH3和NH4+的溶剂化自由能

通过理论计算推测NH2-,NH3和NH4+在水溶液第一溶剂化层中与之直接作用的水分子分别为2,4和4个,并采用离散-连续模型计算了NH2-,NH3,NH3和NH4+在水溶液中的溶剂化自由能.结果表明,由于离散-连续模型在从头算水平考虑了溶质分子与第一溶剂化层溶剂分子之间的作用,能更准确地描述溶剂化作用.此外,采用更加符合溶液中真实情况的溶剂化构型,能得到更准确的溶剂化性质.     

磷酸铝分子筛骨架晶格能与骨架拓扑结构的关系

应用晶格能极小技术计算了１９种磷酸铝分子筛折骨架晶格能，采用一元线性回归分析、多元线性回归分析和人工神经网络误差反传算法（ＢＰ），将其骨架晶格能与骨架拓扑结构参数相关，预测结果与计算晶格能吻合，表明晶格能与配位序（Ｎ２－Ｎ３）具有良好的多元线性关系，利用多元线性回归方程对１０种结构的磷酸铝分子筛的骨架晶格能进行了预测。     

稀土与H2salen配合物的合成与波谱性质

合成了稀土Ｎ，Ｎ－亚乙基双（水杨醛缩亚胺）（Ｈ２ｓａｌｅｎ）双核配合物，通过元素分析、热分析、紫外、红外、远红外光谱、磁化率及１Ｈ、１３ＣＮＭＲ谱与Ｔ１的测定，确定了他们与前人合成的配合物有所不同，其化学组成为［Ｌｎ２（Ｈ２ｓａｌｅｎ）３（ＮＯ３）４］（ＮＯ３）２·３Ｈ２Ｏ（Ｌｎ＝Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ，Ｇｄ，Ｔｂ，Ｅｒ，Ｙｂ及Ｙ），并对它们的配位作用、波谱及可能应用进行了探讨．     

Potential energy surfaces for van der waals complexes of rare gases with H2S and H2S2: Extension to xenon interactions and hyperspherical harmonics representation

This article is an account and extension of a series of recent investigations, which using extensive quantum chemical methods provide analytical hyperspherical representations of the potential energy surfaces for the interactions of rare gases with H₂S as a rigid molecule, and H₂S₂, considered as a floppy molecule with respect to torsional mode. For the H₂S‐rare gas systems, the representation is based on a minimal model, here introduced and discussed. For H₂S₂, the study of the interaction with Xe, not considered previously, completes the series. The results are discussed with reference to the properties and trends expected for interactions of van der Waals type. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

液滴在不互溶液体表面上的相对界面自由能曲面及Neumann三角形的导出

根据系统的界面Helmholtz自由能自发地趋于最低的热力学原理,以浮在不互溶液体(2)表面上透镜状液滴(3)在气(1)、液₂、液₃三相交界处,气-液₃、液₂-液₃界面各自和气-液₂界面通过液滴内部的夹角θ₁、θ₂为变量(0°≤θ₁≤180°,0°≤θ₂≤180°),证明出3个界面张力γ₁₂、γ₁₃、γ₂₃各种可能组合情况下液体₃稳定时的θ₁、θ₂值与它们之间的关系,导出Neumann三角形;并按照计算数据绘出几种类型相对于气相中圆球形液滴的界面自由能曲面图。     

低温等离子体处理化工恶臭污染物硫化氢的研究

采用电晕放电低温等离子体处理模拟硫化氢恶臭气体,考察了输入功率、初始浓度、气体湿度、停留时间等因素对降解效果和能量效率的影响,同时对反应过程进行了动力学研究。研究表明：输入功率以及停留时间对硫化氢降解的影响是积极的,但能量效率随着两者的增加先增大后减小。硫化氢的降解率随着初始浓度的增加而降低,而能量效率随着初始浓度的增加而增加。在气体湿度增加初期,硫化氢降解率和能量效率均随着气体湿度的增加而增加,当气体湿度为50%时达到最大值,然而随着气体湿度的进一步增加,其降解率和能量效率反而降低。对电晕放电低温等离子体处理硫化氢的反应动力学进行了分析,得到硫化氢的反应速率常数为kH2S=0.356 8 m3/（W·h）。     

NC2S+离子的结构和稳定性的理论研究

在密度泛函和从头算理论水平下计算了单重态的NC2S+离子的结构、能量、光谱以及稳定性. 在B3LYP/6-311G(d)水平下, 得到8个异构体, 它们由15个过渡态相连接. 在CCSD(T)/6-311+G(2df)//QCISD/6-311G(d)+ZPVE水平下, 得到能量最低的异构体是直线型的具有1Σ电子态的NCCS+(1)(0.0 kJ/mol), 其次是直线型的异构体CNCS+(2)(54.8 kJ/mol). 两个低能量的异构体1和2及另外一个高能量的直线型异构体CCNS+(3)(323.8 kJ/mol)都具有相当大的动力学稳定性, 这三个异构体在具备一定条件的实验室和星际条件下是可以进行观测的. 分析了这3个异构体的成键性质.     

表观价态异常分子EuS2和Eu2S的泛函理论研究

用密度泛函理论方法研究了EUS2和Eu2S的分子结构、电子结构和成健情况．结果表明EuS2有弯曲构型和直线构型，而Eu2S只有弯曲构型．在S－S和Eu－Eu之间存在化学使．在这两个分子中，Eu和S的价届满足8电子规律，保持其正常价态．第一电离势和原子化能的计算值与实验结果符合较好．相对论效应对分子几何构型和振动基频影响较小，对分子轨道能级顺序和键能有较显著的影响，但旋轨偶合起的作用不大     

镍硫配合物(Me3C+)2Ni(SCH2CH2S)2的合成及结构表征

以NiCl2,Bu4NBr,HSCH2CH2SH为原料合成了配合物(Me3C^ )2Ni(SCH2CH2S)2,其结构经元素分析、IR,UV和^1H NMR确证,X-射线四圆衍射仪测其晶胞参数为：a=0.9127(1)nm,b=1．2424(0)nm,c=1．3906(2),v=1．57685(2)nm^3,z=4,晶体属正交晶系。晶体结构经块状矩阵最小二乘法修正后,最终偏离因子R=0．089。     

The Relationship Between the Retention Time of a Metal and the Free Ligand Concentration of an Eluent in Gel Chromatography

Abstract

It was found that the retention time of magnesium in gel chromatography is expressed as a function of tetrametaphosphate ion concentration in an eluent and the stability constant of the complex. By use of this relation we can evaluate the stability constant of the complex.     

Fluorimetric and molecular mechanics study of the inclusion complex of 2-quinoxalinyl-phenoxathiin with β-cyclodextrin

The complex formed by the inclusion of the polarity-sensitive fluorescent probe 2-[2′-quinoxalinyl]-phenoxathiin (QP) into β-cyclodextrin (β-CD) was investigated by steady-state fluorescence spectroscopy in order to confirm the previously stated intramolecular charge transfer nature of the first excited singlet state of QP. A decrease in the emission intensity in the presence of β-CD was observed and explained on this basis. The 1:1 stoichiometry of the inclusion complex and its association constant of 2,223 M⁻¹ were computed. The QP–β-CD complex was further studied by molecular mechanics (MM+ force field), in order to determine its structure and the type of interactions between QP and β-CD. All possible ways QP could penetrate the β-CD cavity were considered and several structures were generated and optimized. The interaction, binding (van der Waals and electrostatic contributions) and perturbation energies were also calculated. The results have showed that the β-CD cavity incorporates the central part of QP and that complexation is mainly due to van der Waals host–guest interactions.     

Ultra-Large-Scale Screening of Natural Compounds and Free Energy Calculations Revealed Potential Inhibitors for the Receptor-Binding Domain (RBD) of SARS-CoV-2

The emergence of immune-evading variants of SARS-CoV-2 further aggravated the ongoing pandemic. Despite the deployments of various vaccines, the acquired mutations are capable of escaping both natural and vaccine-induced immune responses. Therefore, further investigation is needed to design a decisive pharmacological treatment that could efficiently block the entry of this virus into cells. Hence, the current study used structure-based methods to target the RBD of the recombinant variant (Deltacron) of SARS-CoV-2, which was used as a model variant. From the virtual drug screenings of various databases, a total of four hits were identified as potential lead molecules. Key residues were blocked by these molecules with favorable structural dynamic features. The binding free energies further validated the potentials of these molecules. The TBE for MNP was calculated to be −32.86 ± 0.10 kcal/mol, for SANC00222 the TBE was −23.41 ± 0.15 kcal/mol, for Liriodenine the TBE was −34.29 ± 0.07 kcal/mol, while for Carviolin the TBE was calculated to be −27.67 ± 0.12 kcal/mol. Moreover, each complex demonstrated distinct internal motion and a free energy profile, indicating a different strategy for the interaction with and inhibition of the RBD. In conclusion, the current study demands further in vivo and in vitro validation for the possible usage of these compounds as potential drugs against SARS-CoV-2 and its variants.     

天冬酰胺Schiff碱稀土配合物的合成、表征与抗O-·2性能

合成了天冬酰胺－邻香草醛Schiff碱稀土配合物，用元素分析，摩尔电导率，磁化率测定，差热分析，红外与紫外光谱，1H NMR谱等手段对配合物进行了组成与结构表征，并采用EPR技术对化合物的抗超氧阴离子自由基性能进行了探讨。     

Construction of Hierarchical Hollow Co9S8/ZnIn2S4 Tubular Heterostructures for Highly Efficient Solar Energy Conversion and Environmental Remediation

Visible‐light‐responsive hierarchical Co₉S₈/ZnIn₂S₄ tubular heterostructures are fabricated by growing 2D ZnIn₂S₄ nanosheets on 1D hollow Co₉S₈ nanotubes. This design combines two photoresponsive sulfide semiconductors in a stable heterojunction with a hierarchical hollow tubular structure, improving visible‐light absorption, yielding a large surface area, exposing sufficient catalytically active sites, and promoting the separation and migration of photogenerated charges. The hierarchical nanotubes exhibit excellent photocatalytic H₂ evolution and Cr^VI reduction efficiency. Under visible‐light illumination, the optimized Co₉S₈/ZnIn₂S₄ heterostructure provides a remarkable H₂ generation rate of 9039 μmol h^?1 g^?1 without the use of any co‐catalysts and Cr^VI is completely reduced in 45 min. The Co₉S₈/ZnIn₂S₄ heterostructure is stable after multiple photocatalytic cycles.     

meso-四(邻烷氧基苯基)卟啉及其铜配合物的合成、表征和性能研究

合成了meso-四(邻烷氧基苯基)卟啉及其铜配合物两个系列20个化合物, 其中未见文献报道的化合物16个, 研究了其合成、分离、纯化方法, 得到了这两个系列化合物的晶体或固体, 用¹H NMR, MS, IR, UV, 元素分析等方法确证了这些化合物的结构. 用差示扫描量热法(DSC)和偏光显微镜(PM)研究了这两个系列化合物的液晶性能, 发现19个化合物具有液晶性, 其液晶行为表现为升温单变液晶.     

过渡金属L—丙氨酸夫碱配合物的合成及其抗O^—2性能

合成了Ｌ－丙氨酸缩邻香草席夫碱及其过渡金属Ｃｕ（Ⅱ），Ｃｏ（Ⅱ），Ｎｉ（Ⅱ），Ｚｎ（Ⅱ），Ｃｄ（Ⅱ）和Ｆｅ（Ⅱ）等的配合物，通过元素分析，摩尔电导，红外光谱，电子光谱，热分析及顺磁共振波谱等手段对它们进行了表征，并探讨了它们对Ｏ＾－２的清除作用。     

金属串配合物(n,m)[Cr3(PhPyF)4Cl2](n=2, 3, 4; m=2, 1, 0)的配位结构及其与电场的关系

应用密度泛函理论BP86 方法研究具有分子导线潜在应用的金属串配合物(n, m)[Cr₃(PhPyF)₄Cl₂](HPhPyF=N, N'-苯基吡啶基甲脒; n=2, 3, 4; m=2, 1, 0)的配位结构及其受电场作用的影响, n、m分别表示PhPyF-的苯环在左侧和在右侧的配体个数. 结果表明: (1) 零电场下, 四个PhPyF-的(2, 2)、(3, 1)和(4, 0)三种配位方式能量差别很小, 为竞争态, (2, 2)最稳定. (4, 0)结构中两端轴向配体Cl 均可与Cr 配位, 且Cl₄―Cr1 键比Cl5―Cr3键更强, 若作为分子器件可与电极结合, 这与(4, 0)[CuCuM(npa)₄Cl][PF₆](M=Pd, Pt; Hnpa=2-萘啶苯胺)靠近苯环一端的轴向配体无法与M配位不同. (2) 在(2, 2)、(3, 1)和(4, 0)中, Cr₃⁶⁺链均具有三中心三电子离域σ键, 但离域性逐渐减弱. 随四个PhPyF-配位方式趋于一致, 分子极性逐渐增大, 由Cl₄指向Cl5(Z)方向, Cr1的α自旋密度增大, Cr2 的β和Cr3 的α自旋密度减小. (3) 分子的几何结构和电子结构在电场下发生规律性变化, 在-Z方向电场作用下, (3, 1)、(4, 0)电子移动方向与极性方向相同, 使分子的键长、自旋密度、电荷和能隙变化显著性均大于Z方向电场, 且极性越大变化越显著, 有利于提高分子导电性.     

Morphologies of Spin‐Coated Films of a Library of Diblock Copoly(2‐oxazoline)s and Their Correlation to the Corresponding Surface Energies

Summary: The influence of surface morphologies on the properties of materials is of essential importance and is therefore a widely discussed topic. In the present contribution, the properties of a set of diblock copoly(2‐oxazoline)s are analyzed in terms of their individual morphologies, which have been investigated with tapping‐mode SFM. This collection of diblock copolymers consists of 12 diblock copolymers and four corresponding homopolymers, representing a complete 16‐membered library of (co‐) poly(2‐oxazoline)s, composed of four differently substituted 2‐oxazoline monomers. For the investigated set of compounds, a correlation between the morphologies of the spin‐coated films and their surface energies could be determined.

Morphologies of spin‐coated films of a library of diblock copoly(2‐oxazoline)s and their correlation to the corresponding surface energies.