Nucleophilic reactivity of the peroxide anion in aqueous-alcoholic solutions in the presence of detergents

The reactivity of hydroxide and peroxide anions with 4-nitrophenyl N,N-dimethylcarbamate in aqueous-alcoholic detergent media and in “oil in water” microemulsions has been studied. Aqueous-alcoholic solutions of cationic (CTAB) and neutral (Triton X-100) surface active substances have promise for decomposition of substrates by a nucleophilic mechanism. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 6, pp. 358–363, November–December, 2007.     

拟多维高效液相色谱法分离纯化双峰驼精清中的活性蛋白

利用一种新的高效液相色谱洗脱技术，建立了 ｐＨ缓冲液／离子对二元洗脱模式，对双峰驼精清的两种提取物的反相柱上进行了分离，得到了较纯的活性蛋白组分。该法操作简单、快速、比常规ＨＰＬＣ有更高的选择性及峰容量，并可减少活性蛋白的失活。     

CuO／活性炭和Fe2O3／活性炭催化还原NO

ＣｕＯ／活性炭和Ｆｅ_２Ｏ_３／活性炭催化还原ＮＯ高志明，赵震，杨向光，吴越（中国科学院长春应用化学研究所长春１３００２２）关键词活性炭，还原，ＮＯ，氧化铜，氧化铁目前，对固定源的ＮＯ处理是采用Ｖ２Ｏ５／ＴｉＯ２作催化剂，ＮＨ３作还原剂的选择催化还原方...     

新的手性配体促进的二芳基二酸和联萘酚的不对称合成

由手性配体α-D-葡萄糖衍生物5，6，7以及薄荷醇（8）和葑醇（9），经 Ulmann偶联反应得到光学活性的（R）－和（S）－6，6′－二硝基联苯－2，2′－ 二甲酸（4a),(R)-6,6′-二甲基联苯－2，2′-二甲酸（4b),(R)-1,1′－联萘－2 ，2′－二甲酸（13）。以三个手性膦酰胺16，17，18和CuCl组成的手性络合物为 催化剂，通过2－萘酚直接氧化偶联得到（S）－2，2′－联萘酚（15）。产物4， 13，15具有中等ee值的光学活性。     

The Pharmacophore Hypothesis of Novel Inhibitors for Aurora A Kinase

A three-dimensional pharmacophore model was developed from a series of inhibitors of Aurora A kinase to discover new potent anti-cancer agents using the HypoGen module in the Catalyst software. The pharmacophore model was developed based on the structure of 20 currently available inhibitors, which were carefully selected from the literature. The best hypothesis （Hypo 1） was defined by four features： one hydrogen-bond donor and three hy- drophobic points, with the best correlation coefficient of 0.909, the lowest rms deviation of 1.563, and the highest cost difference of 99.075. The Hypo 1 was then validated by a test set consisting of 24 compounds and by a cross-validation of 95% confidence level through randomizing the data using the CatScramble program, which suggested that a predictive pharmacophore model had been successfully obtained.     

Kinetics and mechanism of gold dissolution in thiourea solutions: Effect of sulfide ions

Chronoamperograms for gold in solutions containing 0.1 M thiourea, 0.5 M H₂SO₄, and catalytically active sulfide ions at the concentration c ₁ from 1 × 10^?5 to 4 × 10^?5 M are obtained at different potentials with the aid of an automated setup intended for renewing the electrode surface directly in the solution by cutting off a thin surface layer of the metal. It is shown that the results of measurements of the current practically coincide at a constant value of the product c ₁ t, where t is the time period elapsed after the renewal of the electrode surface. Such a coincidence testifies to a diffusion nature of processes that hamper accumulation of sulfide ions at the gold surface. This fact permitted the use of a procedure developed previously for the calculation of polarization curves at constant values of surface coverage θ by catalytically active ions. At θ = const, the voltammetric curves for gold in sulfide-containing thiourea solutions are shown to correspond to the Tafel equation. With the surface coverage increasing, the effective values of the exchange current i ₀, transfer coefficient α, and anodic reaction order with respect to thiourea P _a increase from the values i }~ 10^?5 A cm^?2, α }~ 0.12, and P _a = 0.2, which are characteristic of pure solutions, to 2 × 10^?4 A cm^?2, α }~ 0.5, and P _a = 1.1 (at θ }~ 0.5). An interpretation to the established regularities is given.     

超球坐标下原子、分子体系的变分计算：—氦原子和氢负离子基态

应用超球会标表示氦原子和氢负离子的薛定谔方程，将二电子原子在三维空间中的运动转化为单电子原子在六维空间中受广义库仑力作用的运动，我们给出了六维空间广义角动量算符的本征值与本征函数，并以此本征函数微基构造超球波函数，得到超球径微分方程，以广义Laguerre 多项式表示超球径波函数，运用密度矩阵和线性变分法得到非正交基下超球径波函数满足的久期方程，最后求得能量和波函数，计算结果与精确的计算符合良好。     

薄层扫描法测定冬眠过程中刺猬活性组织酶的周期变化

薄层扫描法测定冬眠过程中刺猬活性组织酶的周期变化冯金城（天津师范大学天津３０００７４）孙金生（天津水产研究所天津３００２２１）１前言为了跟踪观察刺猬在冬眠过程中体内乳酸脱氢酶的周期性变化，利用薄层扫描仪测定了其相关的组织同工酶的差异。实践证明，此法简...     

Drug metabolite cluster centers-based strategy for comprehensive profiling of Neomangiferin metabolites in vivo and in vitro and network pharmacology study on anti-inflammatory mechanism

Neomangiferin (NMF) is an extremely special xanthone that could be simultaneously attributed to C-glycoside and O-glycoside with a variety of biological activities, such as anti-inflammatory, antitumor, antipyretic, and so on. So far as we know, the metabolism profiling has been insufficient until now. Herein, Drug Metabolite Cluster Centers (DMCCs)-based Strategy has been developed to profile the NMF metabolites in vivo and in vitro. Firstly, the DMCCs was proposed depending on literature-related and preliminary analysis results. Secondly, the specific metabolic rule was implemented to screen the metabolites of candidate DMCCs from the acquired Ultra High Performance Liquid Chromatography Quadrupole Exactive Orbitrap Mass Spectrometry (UHPLC-Q-Exactive Orbitrap MS) data by extracted ion chromatography (EIC) method. Thirdly, candidate metabolites were accurately and tentatively identified according to the pyrolysis law of mass spectrometry, literature reports, comparison of reference substances, and especially the diagnostic product ions (DPIs) deduced preliminarily. Finally, network pharmacology was adopted to elucidate the anti-inflammatory action mechanism of NMF on the basis of DMCCs. As a result, 3 critical metabolites including NMF, Mangiferin (MF) and Norathyriol (NA) were proposed as DMCCs, and a total of 61 NMF metabolites (NMF included) were finally screened and characterized coupled with 3 different biological sample preparation methods including solid phase extraction (SPE), acetonitrile precipitation and methanol precipitation. Among them, 32 metabolites were discovered in rat urine, 30 in rat plasma, 12 in rat liver, 9 metabolites in liver microsomes and 8 in rat faeces, respectively. Our results also illustrated that NMF primarily underwent deglucosylation, glucuronidation, methylation, sulfation, dihydroxylation and their composite reactions in vivo and in vitro. Additionally, network pharmacology analysis based on DMCCs revealed 85 common targets of disease-metabolites, and the key targets were TNF, EGFR, ESR1, PTGS2, HIF1A, IL-2, PRKCA and PRKCB. They exerted anti-inflammatory effects mainly through the pathways of inflammatory response, calcium-dependent protein kinase C activity, nitrogen metabolism, pathways in cancer and so on. In general, our study constructed a novel strategy to comprehensive elucidate the biotransformation pathways of NMF in vivo and in vitro, and provided vital reference for further understanding its anti-inflammatory action mechanism. Moreover, the established strategy could be generalized to the metabolism and action mechanism study of other natural products.     

Clustering of chemical databases by means of the projection of maximum overlapping sets similarity measurements onto multidimensional spaces

In this paper, we propose a new method for clustering of chemical databases based on the representation of measurements of structural similarity onto multidimensional spaces. The proposed method permits the tuning of the clustering process through the selection of the dimension of the projection space, the normal vectors and the sensibility of the projection process. The structural similarity of each element regarding to the database elements is projected onto the defined spaces generating clusters that represent the characteristics and diversity of the database and whose size and characteristics can be easily adjusted.