Study of complex mixtures of natural substances by the defocusing and dadi methods. VI. Components of the secretion of the pre-anal gland of some poisonous snakes

By mass-spectrometric methods, cholesterol and docosanoic, heneicosanoic, cicosanoic, octadecanoic, cis-octadec-9-enoic, heptadecanoic, hexadecanoic, and pentadecanoic acids have been identified in the odoriferous secretion of the pre-anal glands of the females and males of the common adder and the saw-scaled viper and in those of females of the common mamushi. It has been established that the chemical compositions of the secretions of these glands of the females of the adder, the viper, and the mamushi and of the males of the adder and of the viper are not identical.Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 421–423, July–August, 1986.     

智能聚合物基材料富集磷酸化肽和糖肽的研究进展

翻译后修饰是蛋白质组学研究的前沿和重点,它不仅调节着蛋白质的折叠、状态、活性、定位以及蛋白质间的相互作用,也能帮助科学家更全面地了解生物体的生命过程,为疾病的预测、诊断和治疗提供更加强大的支撑和依据。翻译后修饰产物(例如磷酸化肽和糖肽)丰度很低,且存在着强烈的背景干扰,很难直接用质谱进行分析,因此迫切需要开发高效的富集材料和技术来选择性富集翻译后修饰产物。近年来,智能聚合物基材料通过外部物理、化学或生物刺激可逆地改变其结构和功能,实现对磷酸化肽和糖肽高度可控的吸附和脱附,进而衍生开发出一系列新颖的富集方法,极大地吸引研究者们的兴趣。一方面,智能聚合物基材料的响应变化包括材料疏水性的增加或减少、形状和形貌的改变、表面电荷的重新分布以及亲和配体的暴露或隐藏等特性。这些特性使得目标物和智能聚合物基材料之间的亲和力可以通过简单改变外部条件(如温度、pH值、溶剂极性和生物分子等)实现更可控和更智能的精细调节。另一方面,智能聚合物基材料为集成功能模块提供了便捷的可扩展平台,例如特定的识别组件,显著提高了目标物质的分离选择性。智能聚合物基材料在分离方面展现出巨大的潜力,这为蛋白质翻译后修饰产物的分析和研究带来了希望。围绕上述主题,该文依据Web of Science近20年来近50篇代表性文献,概述了智能聚合物基材料在磷酸化肽和糖肽分离及富集中的发展方向。     

黄鸣龙——我国有机化学的一位先驱

黄鸣龙院士(1898-1979)1919年浙江医药专科学校毕业,1924年德国柏林大学有机药物化学博士;1924-1934年任浙江医专教授、主任,卫生署化学部主任;1934-1940年在欧洲先灵公司等从事研究工作;1940年回国在昆明任中研院化学所研究员,兼任西南联大教授;1945年赴美在哈佛大学,默克公司从事研究工作。1952年绕道欧洲回国,先后在中国人民解放军医学科学院化学系和中国科学院上海有机化学研究所任研究员。1955年当选为中国科学院学部委员(院士)。黄先生一生从事有机化学的教育和研究工作,他在有机化学的“结构与机理”以及“反应和合成”二大方面都作出了在国内外具有深远影响的工作。20世纪40年代黄先生发现了变质山道年4个立体异构体的循环转变,堪称立体化学的经典之作;1948年发表了黄鸣龙还原反应;1952年归国后引领和发展了我国的甾体化学研究,带领了我国甾体药物的生产发展,是我国甾体药物工业的奠基人。黄先生治学严谨,既重视应用研究,又强调基础研究;关注学习新知识、新概念,又更重视实验技术。黄先生教书育人,身体力行,是我国有机化学发展的先驱者和奠基人。     

Ziziphora clinopodioides Lam leaf aqueous extract mediated novel green synthesis of iron nanoparticles and its anti-hemolytic anemia potential: A chemobiological study

In this study, the aqueous extract Ziziphora clinopodioides was used to biosynthesis of iron nanoparticles. A green, productive, and environmentally method was developed for the valuable study and the effective preparation of the green-synthesis of iron nanoparticles using aqueous extracts from the leaf of Ziziphora clinopodioides as a result of reducing and stabilizing factor. The simplicity of the synthesis procedures and easy work up are the benefits of the present study. The structural and morphological characterization of green‐synthesized FeNPs was performed by Uv–Vis. and FT-IR spectroscopy, XRD, SEM, and EDX techniques. The SEM images have exhibited an equal and uniform spherical morphology in size of 30.04. We also investigated the anti-hemolytic anemia property of FeNPs in an animal model of hemolytic anemia. In vivo assay, induction of hemolytic anemia was done by phenylhydrazine in mice. FeNPs significantly reduced the weight and volume of liver and spleen and the concentration of pro-inflammatory cytokines and increased the body weight, the anti-inflammatory cytokines concentration, and the total platelet, WBC, neutrophil, lymphocyte, eosinophil, monocyte, and basophil counts, and RBC parameters as compared to the untreated mice. About the biochemical parameters, FeNPs significantly increased GPx, CAT, and SOD in serum, liver, and spleen, and also HDL, total protein, and albumin in serum, and decreased GR in serum, liver, and spleen, and also erythropoietin, ferritin, ferrous, creatinine, urea, LDL, triglyceride, cholesterol, GGT, ALT, AST, and ALP in serum as compared to the anemic mice. DPPH test revealed similar antioxidant potentials for FeNPs and Butylated hydroxytoluene. FeNPs had low cell viability dose-dependently against HUVEC cell line. It appears that FeNPs can be administrated as a hematoprotective and anti-hemolytic anemia drug or supplement for the treatment of hemolytic anemia in the clinical trial.     

宝日希勒褐煤在合成气与复合溶剂系统下的液化性能研究

在合成气（CO+H₂）与复合溶剂（水+有机溶剂）液化系统下研究了气氛、温度、催化剂类型对宝日希勒褐煤转化率、油气水产率和CO转化率等液化特征的影响,从而探讨其液化性能。结果表明,在高含水复合溶剂系统中,合成气气氛、反应温度430-450℃适宜宝日希勒褐煤液化转化,转化率可达到81.15%,油气水产率达到71.53%。该液化系统下,含铁、碱和硫复合型催化剂能有效地提高液化转化率和油气水产率,在430℃催化液化下褐煤转化率达92.27%,油气水产率达79.39%。该催化剂有效促进了煤中大分子的裂解和系统中水煤气变换反应进程,沥青质减少,油含量增多。液化油中多环芳烃衍生物在催化液化过程中向单环芳烃衍生物和烷烯烃转化,分子量降低,提高了油品质量。     

Free-radical processes in the electrochemical conversion of ecologically harmful gas molecules

Published data and the results of the authors' investigations on the electrochemical conversion of carbon, sulfur, and nitrogen oxides and freons into valuable organic products are reviewed. Considerable attention is paid to the probable mechanisms of such processes, the role and position of the radical-ions and free radicals in them, and the effect of the structure of the reagents, the electrolysis conditions, and other factors on the composition and yield of the products. The problems of developing this promising process, which lies at the junction between physical chemistry, organic chemistry, and ecology, are explored. From the contents of a plenary report at the International Symposium “NATO Workshop on Free Radicals in Biology and Environment” (Bardolina, Italy, June 21–26, 1996) [1]. L. V. Pisarzhevskii Institute of Physical Chemistry, National Academy of Sciences of Ukraine, Kiev. Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 33, No. 5, pp. 268–283, September–October, 1997.     

前列舒通胶囊中26种无机元素的分析

目的：明确造成前列舒通胶囊不同批次间差异的标志性无机元素,并进行安全性评价。方法：采用ICP-MS测定制剂中Al、As、B、Ba、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Mo、Na、Ni、Pb、Sb、Se、Sn、Sr、Ti、Tl、V、Zn和Hg元素含量并进行数据分析。运用主成分及综合评分结合聚类分析手段,确定制剂的特征性元素;进行元素含量和相关性分析,明确不同批次各元素的差异及元素之间的关系;以多元素含量为指标,绘制无机元素谱图。结果：19批样品中均未检测出Se、Mo、Sn、Sb、Tl和Hg,且Pb、Cd、As、Cu、Hg均符合限量标准,无机元素含量谱图趋势一致。主成分分析提取了4个主成分,确定元素B、K、Al、V、Cr、Ca、Ti、Na、Co和Mn可作为特征元素。主成分得分图将19批样品分为两类,聚类分析及综合评分结果与其一致,两类样品中各元素含量存在差异性。相关性分析中,明确了B与K、Al、Cr正相关,K与Cr、Co正相关,V与Cr、Mn正相关,Mn与Co正相关,Ca、Ti、Na两两正相关。结论：通过分析前列舒通胶囊中无机元素含量,确定了特征元素,为前列舒通胶囊质量全面控制研究提供科学依据。     

Mode-coupling study on the dynamics of hydrophobic hydration II: Aqueous solutions of benzene and rare gases

The dynamic properties of both the solute and solvent of the aqueous solution of benzene, xenon and neon are calculated by the mode-coupling theory for molecular liquids based on the interaction-site model. The B-coefficients of the reorientational relaxation and the translational diffusion of the solvent are evaluated from their dependence on the concentration of the solute, and the reorientational relaxation time of water within the hydration shell is estimated based on the two-state model. The reorientational relaxation times of water in the bulk and within the hydration shell, that of solute, and the translational diffusion coefficients of solute and solvent, are calculated at 0-30 degrees C. The temperature dependence of these dynamic properties is in qualitative agreement with that of NMR experiment reported by Nakahara et al. (M. Nakahara, C. Wakai, Y. Yoshimoto and N. Matubayasi, J. Phys. Chem., 1996, 100, 1345-1349, ref. 36), although the agreement of the absolute values is not so good. The B-coefficients of the reorientational relaxation times for benzene, xenon and neon solution are correlated with the hydration number and the partial molar volume of the solute. The proportionality with the latter is better than that with the former. These results support the mechanism that the retardation of the mobility of water is caused by the cavity formation of the solute, as previously suggested by us (T. Yamaguchi, T. Matsuoka and S. Koda, J. Chem. Phys., 2004, 120, 7590-7601, ref. 34), rather than the conventional one that the rigid hydration structure formed around the hydrophobic solute reduces the mobility of water.     

亚胺类共价有机骨架材料在样品前处理中的应用

亚胺类共价有机骨架(I-COFs)是有机单体根据席夫碱(Schiff-base)反应原理缩合形成的一类新型多孔晶体有机材料.I-COFs具有骨架密度低、比表面积大、孔隙率高、单体种类丰富、孔径尺寸可控、结构可功能化、合成方法多样和物化稳定性好等优点.近年来,I-COFs已成为材料科学领域的研究前沿,并广泛用于气体吸附、...     

Control of structure and photophysical properties by protonation and subsequent intramolecular hydrogen bonding

Protonation and subsequent intramolecular hydrogen bonding as methods to control chain structure and tune luminescence in heteroatomic conjugated polymers were reported experimentally [A. P. Monkman et al., J. Am. Chem. Soc. 124, 6049 (2002)]. In this paper, the structure and photophysical properties of the model teraryl compound of phenylene-pyridylene copolymer before and after protonation are theoretically studied with quantum chemistry methods. From the optimized ground states, intramolecular hydrogen bonding to the adjacent oxygen atom in the alkoxy substituent planarizes the backbone of the molecules, and the optimized detailed results of compound 9 before and after protonation, such as the dihedral angles between the central benzene and the two pyridyl rings, the bond lengths, and the bond angles, are consistent with the experimental results. From the results of the calculated excited states, the protonation and subsequent intramolecular hydrogen bonding result in the redshifts of the absorption, the increase of the ionization energy, the increase of the electron affinity, the decrease of the energy difference of the highest occupied molecular orbital and lowest unoccupied molecular orbital, the decrease of the binding gap, and the delocalization of the electron-hole coherence. The photophysical properties of compound 9 before and after protonation are further studied with a three-dimensional real-space analysis method of transition and charge difference densities (study transition dipole moment and charge transfer in the absorption and fluorescence processes) and two-dimensional real-space analysis method of transition density matrices (study the electron-hole coherence and the excitation delocalization). The calculated results show theoretically an insight understanding on the influence of the protonation and subsequent intramolecular hydrogen bonding to chain structure and photophysical properties.     

载体对包埋酶微环境的影响分析

包埋法固定化酶过程中,酶固定化载体的选择和设计是酶固定化过程的关键因素,适宜的载体微环境对酶活性和稳定性的影响尤为重要。论文首先分析并提出了影响固定化酶所处载体微环境的主要因素,包括载体的亲疏水性、结构形态和反应活性。载体的亲疏水性决定固定化酶微环境中的水分含量。载体的结构形态对酶形成的笼效应,以及载体的反应活性,包括共价键合、静电和氢键等的结合能力,影响酶构象的稳定性和运动性。另外,底物／产物的扩散速率和酶的可及性也同样受到载体的孔结构、孔分布以及载体反应活性的影响。本文介绍了常用的酶包埋载体,包括sol-gel二氧化硅、高分子水凝胶以及高分子－二氧化硅杂化凝胶固定化酶过程,结合上述影响酶微环境的因素,分析比较了三类载体固定化酶的包埋率、活性和稳定性,综述了为改善固定化酶微环境所进行改进研究的进展。     

Emulsification of oil in water as affected by different parameters

The aim of this investigation was to develop a basic understanding of the emulsification process by considering simple systems such as n-hexane, n-heptane, n-decane, and kerosene oil in water. The technique employed for the purpose was ultrasonification. The effect of ultrasonification time, chain length, viscosity, surface tension, oil content, and ionic strength of the media on the quality of emulsion has been studied. The emulsions were viewed through microscope to measure the number, size, and size distribution of droplets. Quantification of turbidity and viscosity was also used to characterize the emulsions. It has been found that the number and size of the droplets vary with the time of ultrasonification, contents of oils, molecular mass of the oils, and ionic strength of the media, and hence the quality of the emulsion is influenced by these parameters. The droplet size decreases, whereas the number of drops increases with the time of emulsification, approaching an optimum distribution at about 15 min of ultrasonification. Further, the increase in the molecular mass of the oil increases the size of the droplets and hence decreases the stability of the emulsion. The addition of electrolytes encourages coalescence and enhances the instability in the system. The results are in accord with the equations proposed by us.     

色谱技术在药物-血浆蛋白相互作用研究中的应用进展

小分子药物进入人体血液循环系统后与人血清白蛋白(HSA)、α₁ -酸性糖蛋白(AGP)等血浆蛋白存在广泛的相互作用,这些相互作用深刻影响药物在体内的分布及其与靶标蛋白的结合,进而影响药物效应的发挥。深入探究药物与血浆蛋白间的相互作用对于候选药物的成药性优化、新药研发、联合用药的风险评控等意义重大。而发展高效、灵敏、准确的分析检测方法是开展药物-血浆蛋白相互作用研究的关键。近年来,色谱技术由于其高通量、高分离性能、高灵敏度等特点在该领域得到了广泛的应用,包括测定血浆蛋白翻译后修饰对药物结合的影响,多种药物的竞争性结合等。其中,高效亲和色谱(HPAC)和毛细管电泳(CE)应用最为广泛,能够通过多种分析方法获取结合常数、结合位点数、解离速率常数等相互作用信息。该文着重综述了HPAC和CE在药物-血浆蛋白相互作用研究中的常用策略及最新研究进展,包括HPAC中常用的前沿色谱法、竞争洗脱法、超快亲和提取法、峰值分析法和峰衰减分析法,以及CE中常用的亲和毛细管电泳法(ACE)和毛细管电泳前沿分析法(CE-FA)等。最后,该文还对当前色谱方法存在的不足进行了总结,并对色谱技术在药物-血浆蛋白相互作用研究领域的应用前景和发展方向进行了展望。     

Functionalized tellurols: synthesis, spectroscopic characterization by photoelectron spectroscopy, and quantum chemical study

Ethene-, cyclopropane-, 3-butene-, and cyclopropanemethanetellurol have been synthesized by reaction of tributyltin hydride with the corresponding ditellurides and characterized by 1H, 13C, and 125Te NMR spectroscopy and high-resolution mass spectrometry. The tellurols of this series, with a gradually increasing distance between the tellurium atom and the unsaturated group, have been studied by photoelectron spectroscopy and quantum chemical calculations. Two stable conformations of ethenetellurol and cyclopropanetellurol, five of allyltellurol, and four of cyclopropanemethanetellurol were found. In the photoelectron spectrum of vinyltellurol, the huge split between the first two bands indicates a direct interaction between the tellurium lone electron pair and the double bond. In the allyl derivative, a hyperconjugation effect was found for the most stable conformers. In contrast to the vinyl compounds, no direct interaction between the lone electron pair of X (X = O, S, Se, and Te) and the three-membered ring could be observed in the cyclopropyl derivatives. A hyperconjugation-like effect, which is independent of the relative orientation of the X-H group, is found to increase from S to Te. Thus, the type and extent of the interaction between the TeH group and an unsaturated or cyclopropyl moiety are clarified while the first comparison of interactions between the nonradioactive unsaturated chalcogen derivatives is performed.     

Effect of cholesterol and other additives on viscosity, self-diffusion coefficient, and intramolecular movements of oleic acid

It has been empirically known that cholesterol largely increases the viscosity of oleic acid. To clarify the mechanism of the effect of cholesterol on the intermolecular and the intramolecular (segmental) movements of oleic acid in the liquid state, we measured density, viscosity, IR, 1H NMR chemical shift, self-diffusion coefficient, and 13C NMR spin-lattice relaxation time for the liquid samples of oleic acid containing a small amount of cholesterol. Furthermore, the above measurements were also carried out for the samples of oleic acid containing a small amount of cholestanol, cholestane, cholesteryl oleate, ethanol, or benzene. Cholesterol, possessing one OH group and one double bond in its molecular structure, largely increased the viscosity and reduced the self-diffusion and the intramolecular movement of oleic acid. Cholestanol, possessing one OH group but not a double bond, and cholesteryl oleate, not possessing an OH group, also reduced the self-diffusion and the intramolecular movement; cholestane, not possessing an OH group, slightly reduced the self-diffusion and the intramolecular movements. In contrast with these sterols, ethanol and benzene reduced the viscosity and increased the self-diffusion and the intramolecular movements. In addition, cholesterol and ethanol, both having one OH group, promoted the upfield shift of the 1H NMR signal of the carboxyl group of oleic acid; IR difference spectra for the cholesterol/oleic acid system quite resemble those for the ethanol/oleic acid system. These results suggest that oleic acid makes a complex with cholesterol as well as with ethanol. On the basis of the formation of the complex, we have revealed the role and the functional mechanism of cholesterol to the intermolecular and the intramolecular movements of oleic acid in the liquid state.     

Protein content, activity and amino acid composition of proteinase inhibitors of seeds of some varieties of pea and their hybrids

The results are given of a study of the quantitative content of protein in the seeds of some pea varieties and mutants, the activity of the total inhibitor proteins, and correlations of their activity with the protein content of the seeds and the amino acid compositions of the proteinase inhibitors. Considerable differences have been found in the amounts of a number of amino acids of the protein inhibitors of parental varieties and mutants of the pea, the amounts of serine, glutamic acid, alanine, and valine correlating positively with the inhibitor activity.Institute of Plant Physiology and Biophysics, Tadzhik SSR Academy of Sciences, Dushanbe. V. I. Nikitin Institute of Chemistry, Tadzhik SSR Academy of Sciences, Dushanbe. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 399–404, May–June, 1988.     

在还原剂存在下CO2作为碳源合成苯并噻唑反应的研究进展

CO₂是一种来源丰富、价廉易得的C1资源。将CO₂高值化利用是“双碳”目标实现的途径之一。苯并噻唑类化合物广泛应用于医药、农药等领域。因此,从绿色和可持续发展角度来看,利用CO₂作为碳源合成杂环化合物苯并噻唑具有重要的意义。本文综述了氢气、硅烷和硼烷三类还原剂还原CO₂与邻氨基苯硫酚反应合成苯并噻唑的方法,分析了各种方法的优缺点,阐述了采用不同还原剂的反应机理,并指出了这一领域面临的问题。另外,对该领域未来的发展方向进行了展望,如绿色环保溶剂的使用、新型高效还原剂的研究、苯并噻唑新合成路线的设计等。     

常见茶叶中14种元素含量分析及重金属风险评价

采集传统名茶地标产品样品各3种为实验样品,通过ICP-OES和ICP-MS对样品进行K、Ca、Mg、Mn、B、Cu、Fe、Ni、Zn、Cr、Co、Cd、As、Pb等14种元素的含量测定。利用单因素方差分析、主成分分析、污染评价等方法,对茶叶无机元素含量进行分析和污染评价,并对污染来源进行了研究。结果表明,不同产地茶叶样品中的K、Ca、Mg、Mn、Fe等元素含量差异较大;食品及茶叶安全限量元素Cd、Cr、Pb、As等实测值均未超过国家标准限值;部分元素之间具有正相关性,如Cu与Cd, Cu与Ni, As与Ni两两之间关联性较强;从主成分分析看出Cu、Cd、As和Ni为PC1代表因子,K和Fe分别为PC2和PC3的代表因子,PC1主要代表了金属冶炼、工业排放和垃圾焚烧等方面的贡献,PC2和PC3分别代表了肥料施放和茶叶加工等方面的贡献。     

甲烷/甲醇光催化转化研究进展

在能源需求不断上涨及石油供应日益紧张的背景下,开展对煤、天然气或生物质等非油基资源(CO、CO_2、CH_3OH、CH_4等)的高效利用显得尤为重要。C_1小分子(CO、CO_2、CH_3OH、CH_4等)经催化转化可得到燃料及多种化学品,一直受到学术界及工业界的广泛关注。甲烷/甲醇作为重要的C_1平台分子,其催化转化在C_1化学中占据重要地位。为了提高目标产物的选择性,需要有效地控制甲烷/甲醇中C―H键的活化。传统热催化作为甲烷/甲醇最常见的转化方法发展已久,但仍然面临着反应条件苛刻、能耗大、产率和选择性低等问题。光催化反应通过引入光能弥补反应中吉布斯自由能的上升,同时具有反应条件温和、操作简单、能耗低等特点,从而为甲烷/甲醇转化提供了新的途径。通过调节光的波长、强度以及催化剂的氧化能力可以实现甲烷/甲醇的选择性转化,减少副产物的生成。此外,光催化能够选择性活化甲醇的C―H键而非O―H键,从而实现甲醇的C―C偶联反应。本文主要围绕甲烷/甲醇的重整、氧化和偶联反应,总结近年来的光催化转化进展,并对进一步提高光催化性能做了展望。