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Science China Chemistry 2010年第4期53卷 797-806页

作者： XU Kun, YANG XiaoDa & WANG Kui state key laboratory for natural and biomimetic drugs Department of Chemical Biology, School of Pharmaceutical Sciences, peking university Health Science Center, Beijing 100191, China state key laboratory for natural and biomimetic drugs Peking University Health Science Center Beijing China Department of Chemical Biology School of Pharmaceutical Sciences Peking University Health Science Center Beijing China

Calmodulin (CaM) is a multifunctional Ca2+-binding protein regulating the activity of many enzymes in response to fluctuation of the intracellular Ca2+ level. It has been shown that a CaM Q41C/K75C mutant (CaMSS) with a disulfide bond in the N-terminal domain exhibits greatly reduced affinity to Ca2+. In the present study, the experimental results revealed a unique metal binding pattern in CaMSS towards La3+ and Ca2+ separately: the mutant protein binds Ca2+ at site Ⅰ, Ⅲ and IV; however, it binds La3+ at site Ⅰ, Ⅱ and IV. A putative mechanism was proposed which is the conformation of site Ⅱ (or siteⅢ) of CaMSS could be altered and thus loses its metal ion affinity in response to metal binding in the opposite terminal domain possibly through the long range domain interaction. The present work may offer new perspectives for understanding the mechanisms of specific metal ion affinity in CaM and for CaM-based protein design.

关键词： calmodulin lanthanum calcium long range interaction

Brain-derived neurotrophic factor protects neurons from GdCl_3-induced impairment in neuron-astrocyte co-cultures

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中国科学：化学英文版 2010年第10期53卷 2193-2199页

作者： XIA Qing, FENG XuDong, YUAN Lan, WANG Kui & YANG XiaoDa state key laboratory of natural and biomimetic drugs and Department of Chemical Biology School of Pharmaceutical Sciences, peking university, Beijing 100191, China state key laboratory of natural and biomimetic drugs and Department of Chemical Biology School of Pharmaceutical Sciences Peking University Beijing China

Gadolinium (Gd3+) complexes are important contrast agents in medical magnetic resonance imaging (MRI) and of great potential value in brain research. In order to better understand the mechanisms of the action of Gd3+ on neurons in the complex central nervous system (CNS), the neurotoxic actions of GdCl3 have been investigated in both neuron monoculture and astrocyte-neuron co-culture systems. Measurements of lactate dehydrogenase release showed that GdCl3 causes significant cell death of monocultured neurons as a result of reactive oxygen species (ROS) generation and down-regulation of brain-derived neurotrophic factor (BDNF). However, GdCl3 does not affect the viability and BDNF expression of astrocytes. Both co-culturing of neurons with astrocytes and addition of BDNF ameliorated GdCl3-induced neurotoxicity by decreasing ROS generation and facilitating recovery of BDNF levels. The results obtained suggest that astrocytes in the CNS may protect neurons from GdCl3-induced impairment through secreting BDNF and thus up-regulating BDNF expression and interfering with Gd3+-induced cell signaling in neurons. A possible molecular mechanism is suggested which should be helpful in understand- ing the neurotoxic actions of gadolinium probes .

关键词： gadolinium brain-derived neurotrophic factor BDNF co-culture astrocytes neurons

Some interesting CH_2CH_3 spin systems in several diethyl malonate indene derivatives studied with NMR and molecular modeling

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Science China Chemistry 2009年第7期52卷 937-942页

作者： ZHANG Long1, HE WeiWei1, LIANG YongMin2 & CUI YuXin1 1 state key laboratory of natural and biomimetic drugs, School of Pharmaceutical Sciences, peking university, Beijing 100191, China 2 state key laboratory of Applied Organic Chemistry, Lanzhou university, Lanzhou 730000, China state key laboratory of natural and biomimetic drugs School of Pharmaceutical Sciences Peking University Beijing China state key laboratory of Applied Organic Chemistry Lanzhou University Lanzhou China

While studying the electrophilic cyclization of acetylenic malonates in synthesizing malonate indene derivatives with high regio and stereo-selectivity, we found that the CH2 and CH3 protons of two COOCH2CH3 groups in some diethyl malonate indene derivatives showed very interesting spin-spin coupling and signal multiplicity. To explain those phenomena, we synthesized several diethyl malonate indene derivatives, and then used 1H NMR spectra and molecular modeling to investigate the CH2CH3 spin system of these two COOCH2CH3 groups in detail. The results showed that the spin systems of CH3CH2 of the two COOCH2CH3 groups in those compounds may exist in different froms (AMX3, ABX3 and A2X3), and the effect of the aromatic ring induced by the phenyl group at the end of the triple bond is the main reason responsible for those phenomena.

关键词： electrophilic cyclization spin-spin coupling signal multiplicity molecular modeling spin system aromatic ring

Tetra-n-butylammonium Hydroxide:an Efficient Catalyst for N-Alkylation of Pyrimidines and Purines

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Chemical Research in Chinese Universities 2006年第4期22卷 451-454页

作者： ZHANG Zhi-li~ , ZHOU Shou-xin, WANG Xiao-wei, WANG Hong-tao, CHEN Yan-li and LIU Jun-yi Department of Chemical Biology, School of Pharmaceutical Sciences state key laboratory of natural and biomimetic drugs, peking university, Beijing 100083, P. R. China Department of Chemical Biology School of Pharmaceutical Sciences state key laboratory of natural and biomimetic drugs Peking University Beijing 100083 P. R. China

An efficient procedure for N-alkylation of pyrimidines and purines in the presence of tetra-n-butylammonium hydroxide（TBAH） is described. The method is very practical and the alkylation can occur at room temperature... 详细信息

关键词： Tetra-n-butylammonium hydroxide N-Alkylation Purine Pyrimidine

The Construction of Numerical Scheme forHyperbolic Equation and Exact Considerationof Numerical Diffusion and Dispersion

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 156-162页

作者： Qingdong CAI(state key laboratory for Turbulence Research, peking university, Beijing 100871, China) state key laboratory for Turbulence Research Peking University Beijing 100871 China

A new technique in the formulation of numerical scheme for hyperbolicequation is developed. It is different from the classical FD and FE methods. We begin withthe algebraic equations with some undefined parameters, and get the difference equationthrough Taylor-series expansion. When the parameters in the partial difference equationare defined, the equation is what the scheme will simulate. The numerical example ofthe viscous Burgers equation shows the validity of the scheme. This method deals withthe numerical viscosity and dispersion exactly, giving a preliminary explanation to someproblems that the CFD face now.

关键词： modified equation Taylor expansion consistency truncation error

3D-QSAR study on phenoxy-alkylamine compounds of α_1-adrenoceptor antagonist

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Chinese Science Bulletin 2001年第4期46卷 303-306页

作者： FANG Hao, LU Jingfen, XIA Lin & ZHANG LineDepartment of Medicinal Chemistry, China Pharmaceutical university, Nanjing 210009, China state key laboratory of natural and biomimetic drugs, Beijing Medical university, Beijing 100083, China Department of Medicinal Chemistry China Pharmaceutical University Nanjing China state key laboratory of natural and biomimetic drugs Beijing Medical University Beijing China

The study of three-dimensional quantitative structure-activity relationship (3D-QSAR) of DDPH and its derivatives that have been known with their activity parameters has been developed using the comparative molecular field analysis (CoMFA) method. Here, (+)-DDPH crystal structure was selected as the active conformation model and comparisons between the influences of different charge calculation methods and grid setup were conducted. The coefficients of cross-validation (q2) and regression (r2) are 0.481 and 0.997, respectively. The standard error (SE) is 0.102. The research result suggests that the steric field makes more contributions to the activity than the electrostatic field. This model can help us not only in improving our understanding of the receptor-ligand interactions, but also in predicting the activity of derivatives and designing new compounds with better potency.

关键词： CoMFA. α1 -adrenoceptor antagonist.

A New Efficient Synthesis of Bisphenol A Diether Bis-imidazoles and Bis-benzimidazoles

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Chinese Chemical Letters 1998年第10期9卷 917-918页

作者： Cheng He ZHOU Jun WEI Zhong Jun LI Ru Gang XIE Meng Shen CAI( Department of Bioorganic Chemistry, state key laboratory of natural and biomimetic drugs,School of Pharmaceutical Sciences, Beijing Medical university, Beding 100083 Depotment of Chemistry state key Lab. Nat. biomimetic drugs School of Pharmaceutical Sciences Beijing Medical University Beijing 100083 China Department of Chemistry School of Sciences Sichuan Union University Chengdu 610064 China

A new efficient synthesis of bisphenol A diether bis-imidazoles and bis-benzimidazoles by bromoalkylation and imidazolylation or benzimidazolylation two-step reactions from commercial bisphenol A, imidazole, 2-methyli... 详细信息

关键词： bisphenol A imidazole benzimidazole ether synthesis

The synthesis, bioactivity and paramagnetic resonance of angiotensin Ⅱ and its spin labelled derivative

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Chinese Science Bulletin 1997年第21期42卷 1843-1846页

作者： WANG Rui, LI Xiaoxu, HU Xiaoyu, NI Jingman, LI Changling and LU Jingfen1. Department of Biology, state key laboratory of Applied Organic Chemistry, Lanzhou 730000, China 2. Department of Chemistry, Lanzhou university, Lanzhou 730000 3. state key laboratory of natural and biomimetic drugs, Beijing Medical U-niversity, Beijing 100083, China. Department of Biology State Key Laboratory of Applied Organic Chemistry Lanzhou China Department of Chemistry Lanzhou University Lanzhou state key laboratory of natural and biomimetic drugs Beijing Medical University Beijing China

ANGIOTENSIN Ⅱ(Ang Ⅱ) is an important constituent in renin-angiotension system (RAS).The amino acid sequence of Ang Ⅱ is DRVYIHPF. Ang Ⅱ plays an important role both inmaintenance of normal blood pressure and in occurrence of hypertension. Ang Ⅱ binding re-ceptor can induce many kinds of physiological effects. Spin labeling is an effective method thatgreatly deepened the knowledge in structure, movement and interaction of biologicalmolecules. For example, it has been used in studying interaction of antigen and antibody suc-

关键词： spin labelled angiotensin Ⅱ solid phase peptide synthesis bioactivity electron spin resonance.

Universal hierarchical symmetry for turbulence and general multi-scale fluctuation systems

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Acta Mechanica Sinica 2009年第3期25卷 279-294页

作者： Zhen-Su She Zhi-Xiong Zhang state key laboratory for Turbulence and Complex Systems, College of Engineering, peking university, 100871 Beijing, China state key laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing China

Scaling is an important measure of multi-scale fluctuation systems. Turbulence as the most remarkable multi-scale system possesses scaling over a wide range of scales. She-Leveque （SL） hierarchical symmetry, since its publication in 1994, has received wide attention. A number of experimental, numerical and theoretical work have been devoted to its verification, extension, and modification. Application to the understanding of magnetohydrodynamic turbulence, motions of cosmic baryon fluids, cosmological supersonic turbulence, natural image, spiral turbulent patterns, DNA anomalous composition, human heart variability are just a few among the most successful examples. A number of modified scaling laws have been derived in the framework of the hierarchical symmetry, and the SL model parameters are found to reveal both the organizational order of the whole system and the properties of the most significant fluctuation structures. A partial set of work related to these studies are reviewed. Particular emphasis is placed on the nature of the hierarchical symmetry. It is suggested that the SL hierarchical symmetry is a new form of the self-organization principle for multi-scale fluctuation systems, and can be employed as a standard analysis tool in the general multi-scale methodology. It is further suggested that the SL hierarchical symmetry implies the existence of a turbulence ensemble. It is speculated that the search for defining the turbulence ensemble might open a new way for deriving statistical closure equations for turbulence and other multi-scale fluctuation systems.

关键词： Turbulence. Scaling law. She-Leveque modelHierarchical symmetry Self-organization - Turbulenceensemble