2,6-二氯嘌呤核苷的合成工艺研究

以2,6-二氯嘌呤和1,2,3,5-四乙酰核糖为原料,四氯化锡为催化剂,130℃下反应18min,得到中间体2,6-二氯嘌呤-2',3',5'-三乙酰基核苷。该中间体在硫酸-甲醇中脱酰基得到2,6-二氯嘌呤核苷,为白色粉状结晶,收率63%,纯度(HPLC)≥99.0%,熔点152￣154℃。     

Potassium–copper and potassium–cobalt catalysts supported on alumina for simultaneous NOx and soot removal from simulated diesel engine exhaust

This paper deals with the activity of bimetallic potassium–copper and potassium–cobalt catalysts supported on alumina for the reduction of NO_x with soot from simulated diesel engine exhaust. The effect of the reaction temperature, the soot/catalyst mass ratio and the presence of C₃H₆ has been studied. In addition, the behavior of two monometallic catalysts supported on zeolite beta (Co/beta and Cu/beta), previously used for NO_x reduction with C₃H₆, as well as a highly active HC-SCR catalyst (Pt/beta) has been tested for comparison. The preliminary results obtained in the absence of C₃H₆ indicate that, at temperatures between 250 and 400 °C, the use of bimetallic potassium catalysts notably increases the rate of NO_x reduction with soot evolving N₂ and CO₂ as main reaction products. At higher temperatures, the catalysts mainly favor the direct soot combustion with oxygen. In the presence of C₃H₆, an increase in the activity for NO_x reduction has been observed for the catalyst with the highest metal content. At 450 °C, the copper-based catalysts (Cu/beta and KCu2/Al₂O₃) show the highest activity for both NO_x reduction (to N₂ and CO₂) and soot consumption. The Pt/beta catalyst does not combine, at any temperature, a high NO_x reduction with a high soot consumption rate.     

二环己基并-18-冠-6合成工艺的改进

报道了改进的二环己基并-18-冠-6(DCH-18-C-6)合成方法,并用该法实现了DCH-18-C-6的工业规模合成。对由二苯并-18-冠-6加氢合成DCH-18-C-6的反应中使用的Picher-钌催化剂进行了改性,用pH 3~5条件下新制备的Picher-钌催化剂,将反应温度提高并控制在130~140℃之间,可使氢化产率由文献报道的最高65%提高到85%以上,还显著提高了产物中DCH-18-C-6的立体异构体A(cis-syn-cis)含量。建立了用气相色谱法测定DCH-18-C-6异构体含量的方法,并用正庚烷进行结晶以实现A(cis-syn-cis)的提纯。     

吡啶并吡唑类化合物与蛇毒蛋白的相互作用

运用荧光猝灭的原理在p H 7.6的生理条件下,眼镜蛇毒蛋白与系列6-氨基-4-芳基-5-氰基-3-甲基-1-苯基吡啶[2,3-c]并吡唑化合物之间的相互作用被研究,并且筛选出6-氨基-4-对羟基苯基-5-氰基-3-甲基-1-苯基吡啶[2,3-c]并吡唑（I）进行了详细研究。猝灭常数KSV、结合常数K以及结合位点n被获得。该实验证明眼镜蛇毒蛋白与I之间生成了新的化合物,而这一过程是静态猝灭的过程,并且它们之间存在着一定的结合。     

Combinatorial Measurement of CDKN1A/p21 and KIF20A Expression for Discrimination of DNA Damage-Induced Clastogenicity

In vitro mammalian cytogenetic tests detect chromosomal aberrations and are used for testing the genotoxicity of compounds. This study aimed to identify a supportive genomic biomarker could minimize the risk of misjudgments and aid appropriate decision making in genotoxicity testing. Human lymphoblastoid TK6 cells were treated with each of six DNA damage-inducing genotoxins (clastogens) or two genotoxins that do not cause DNA damage. Cells were exposed to each compound for 4 h, and gene expression was comprehensively examined using Affymetrix U133A microarrays. Toxicogenomic analysis revealed characteristic alterations in the expression of genes included in cyclin-dependent kinase inhibitor 1A (CDKN1A/p21)-centered network. The majority of genes included in this network were upregulated on treatment with DNA damage-inducing clastogens. The network, however, also included kinesin family member 20A (KIF20A) downregulated by treatment with all the DNA damage-inducing clastogens. Downregulation of KIF20A expression was successfully confirmed using additional DNA damage-inducing clastogens. Our analysis also demonstrated that nucleic acid constituents falsely downregulated the expression of KIF20A, possibly via p16 activation, independently of the CDKN1A signaling pathway. Our results indicate the potential of KIF20A as a supportive biomarker for clastogenicity judgment and possible mechanisms involved in KIF20A downregulation in DNA damage and non-DNA damage signaling networks.     

大分子界面改性剂对PA6/水镁石力学性能的影响

通过力学性能测试及扫描电子显微镜分析,探讨了自制的大分子界面改性剂对PA6／水镁石力学性能的影响,并与偶联剂TC-114进行了对比。结果表明,加入大分子界面改性剂与偶联剂TC-114相比,可以明显提高PA6／水镁石的力学性能,特别是断裂伸长率和冲击强度提高较大。     

高温高压水条件下尼龙6的分解及其动力学研究

用水作为反应介质,研究了尼龙(PA)6在高温高压水中的分解行为,采用傅里叶变换红外光谱对其固相产物进行了分析,采用液相色谱利用外标法对其液相产物进行了分析。结果表明,固相产物为未分解的PA6,而绝大部分的液相产物为ε—己内酰胺。考察了不同的反应压力、温度、反应时间对分解反应的影响,证明提高温度、延长时间、增加压力有利于PA6的水解。采用紫外分光光度计对得到的ε—己内酰胺进行定量分析,并通过Arrhenius公式计算得到其在亚临界条件下的活化能为41．98kJ／mol。     

3,4-二氢-2(1H)喹啉酮衍生物的合成研究

对3,4-二氢-2(1H)喹啉酮衍生物1,2,3(R= NO2,NH2,OH;R= H,NO2,NH2)的合成进行了研究。以苯胺和3-氯丙酰氯为原料,制得N-苯基-3-氯丙酰胺,然后经环合得到3,4-二氢-2(1H)喹啉酮,再经由硝化、还原、重氮化水解合成了一系列3,4-二氢-2(1H)喹啉酮衍生物:6-硝基-3,4-二氢-2(1H)喹啉酮(1a),6,8-二硝基-3,4-二氢-2(1H)喹啉酮(1b),6-氨基-3,4-二氢-2(1H)喹啉酮(2a),6,8-二氨基-3,4-二氢-2(1H)喹啉酮(2b),6-氨基-8-硝基-3,4-二氢-2(1H)喹啉酮(2c),6-羟基-3,4-二氢-2(1H)喹啉酮(3a)和6-羟基-8-硝基-3,4-二氢-2(1H)喹啉酮(3b),其中化合物(2c)及(3b)为新化合物。单步产率均在86%以上,路线简单,操作简便,反应条件温和。采用MS,1HNMR对产品进行了定性及结构表征。     

Inorganic polymers made of fayalite slag: On the microstructure and behavior of Fe

The microstructure of inorganic polymers (IP) formed from fayalite slag was investigated as a function of the composition of different activating solutions. The starting slag was 80 wt% amorphous, and after activation using sodium silicate solutions with varying SiO₂/Na₂O molar ratios, the amorphous phase dissolved and a binder phase was formed. The morphology of this binder, including the population and size of remnant particles and pores, was dependent on the particular activating solution used, and became denser as the level of silicate rose. ⁵⁷Fe Mössbauer spectroscopy revealed that the IP synthesis reaction is combined with the oxidation of Fe²⁺ from the fayalite slag to Fe³⁺ in the inorganic polymer binder. The reaction extent varied and could be quantified using the absorption areas of these ions. Data corroborate that the Fe²⁺ ions in the amorphous part of the fayalite slag and the Fe³⁺ ions in the new binder phase had an average oxygen‐coordination number of 5.     

Generation of hydrogen under visible light irradiation with enhanced photocatalytic activity of Bi2WO6/Cu1.8Se for organic pollutants under Vis‐NIR light reign

To make better use of solar light, a new Bi₂WO₆/Cu_1.8Se photocatalyst active to visible and near‐infrared light has been synthesized by a facile hydrothermal method. The composites were characterized by X‐ray diffractometry (XRD), scanning electron microscopy (SEM), UV‐vis diffuse reflectance spectroscopy (DRS), and photoluminescene (PL). The photocatalytic activities of Bi₂WO₆/Cu_1.8Se are evaluated by degrading Congo red solution and hydrogen generation from water. It was found that the molar percentage of Cu_1.8Se had great effects on the morphology and photocatalytic property of the Bi₂WO₆/Cu_1.8Se heterojunctions, and the composite with suitable molar amount of Cu_1.8Se exhibits much enhanced photocatalytic activity for Congo red degradation under visible and near‐infrared light irradiation and for hydrogen generation under visible light compared to Bi₂WO₆. The significant improvement photocatalytic activity of the composite could be attributed to its good light absorption, suitable band gap structure, and effective separation of photogenerated electron‐hole pairs of Bi₂WO₆/Cu_1.8Se heterojunction. This work presents an efficient multifunction photocatalyst owning the activity both for water splitting under visible light and for organic contaminants decomposition under visible‐near‐infrared light.