4-(色酮-3-基)-3-乙氧羰基-1,4,5,6,7,8-六氢-5-氧代-2,7,7-三甲基喹啉的一步合成

报道了用3-甲酰基色酮、5,5-二甲基-1,3-环己二酮、乙酰乙酸乙酯与醋酸铵一步法合成4-(色酮-3-基)-3-乙氧羰基-1,4,5,6,7,8-六氢-5-氧代-2,7,7-三甲基喹啉类化合物, 对其结构进行了表征, 并分析了代表性化合物2f的晶体结构. 2f晶体属于单斜晶系, P2/c空间群, 所得晶胞参数为: a＝2.0255(4) nm, b＝0.9132(2) nm, c＝1.4066(3) nm, β＝121.60(3)°, V＝2.2159(8) nm³, Z＝4, D_c＝1.335 g/cm³, μ＝0.209 mm^－1, F(000)＝736, R₁＝0.0556, wR₂＝0.1248.     

新型3-萘基-1,3-噻唑烷-4-酮衍生物的微波促进合成及其抗菌活性研究

利用微波促进的多组分一锅法, 在封管条件下, 以萘胺、芳醛和巯基乙酸为原料, 4-二甲氨基吡啶(DMAP)/N,N’-二环已基碳二亚胺(DCC)为催化剂, 合成了系列新的噻唑烷酮衍生物, 该反应具有时间短、操作简便等优点. 目标化合物通过IR, NMR, MS和元素分析等方法确定结构. 初步测试了化合物对丁香假单胞杆菌黄瓜角斑病菌致病变种、番茄灰霉病菌和黄瓜白粉病菌抑制活性, 结果表明: 部分化合物对黄瓜白粉病菌有显著抑制作用, 但对前两种植物病菌抑制效果不明显.     

基于羧基化聚吡咯-氯化血红素和点触发链置换反应信号放大的电化学生物传感器检测转基因作物中CaMV35S序列

为适应快速增长的转基因生物(GMOs)安全评价与管理的需求,高效、可靠的转基因检测技术研究与应用的重要性日益凸显。该文采用一步法合成了羧基化聚吡咯(cPPy)与氯化血红素(Hemin)的纳米复合物(cPPy-hemin),并以其为信号标签合成了一种DNA双链结构功能化的纳米信标(DNA-cPPy-hemin)。利用cPPy-hemin增强的模拟酶催化活性,结合点触发链置换反应(TSDR)信号放大策略,制备了一种新型电化学基因传感器用于转基因成分的灵敏检测。通过信号探针(Ps)与模板链(Ts)、辅助链(As)结合形成DNA双链体结构中的-NH2功能化cPPy-hemin,制备Ts/As/Ps-cPPy-hemin双链DNA结构的纳米信标。在目标花椰菜花叶病毒35S启动子(CaMV35S)序列和燃料链(Fs)存在下,TSDR过程释放出的Ps-cPPy-hemin与固定在电化学沉积金纳米粒子修饰GCE表面上巯基化的DNA捕获探针(Cs)相结合,利用cPPy-hemin对H₂O₂的模拟酶催化产生的电信号,可实现对CaMV35S的定量检测。在最优条件下...     

Detection and Sequence Identification of Dinucleotides Produced from N‐Phosphoryl Alanine and Four Nucleosides by HPLC‐ESI‐MS/MS

本文利用液相色谱质谱联用技术研究了N－磷酰化丙氨酸和四种核苷（腺苷,尿苷,胞苷和鸟苷）的模板反应产物。结果表明生成了不同类型的单核苷酸和二核苷酸,并且生成的二核苷酸序列也得到了确证。研究结果揭示,二核苷酸骨架裂解形成的c离子可以作为确证二核苷酸序列的诊断离子。本文首次证明不论是在正离子模式还是在负离子模式下,c离子都可以用来确定此反应体系中生成的二核苷酸产物的序列。     

Novel Strong Cation‐exchange Monolithic Column Using Poly(vinyl ester resin) as Stationary Phase Materials for Lysozyme Separation by HPLC

本实验合成了一种以聚乙烯基酯树脂为原料的聚合物整体柱。在聚合反应中,聚乙烯基酯树脂在聚合中既作为单体同时也作为交联剂,偶氮二异丁腈作为引发剂,十六醇为致孔剂。聚合物制得后以扫描电镜考察了该聚合物的内部形态。同时联合高效液相色谱分别考察了该整体柱的分离能力和载样量。在分离实验中,考察了流动相的浓度及pH值对分离效果的影响。结果表明,溶菌酶可成功的从鸡卵清中分离出,并在较短的时间内取得了较好的分离效果。     

Novel Flower‐Like Ag‐SiO2‐MgO‐Al2O3 Material: Preparation,Characterization and Catalytic Application in Methanol Dehydrogenation

Catalytic direct dehydrogenation of methanol to formaldehyde was carried out over Ag‐SiO₂‐MgO‐Al₂O₃ catalysts prepared by sol‐gel method. The optimal preparation mass fractions were determined as 8.3% MgO, 16.5% Al₂O₃ and 20% silver loading. Using this optimum catalyst, excellent activity and selectivity were obtained. The conversion of methanol and the selectivity to formaldehyde both reached 100%, which were much higher than other previously reported silver supported catalysts. Based on combined characterizations, such as X‐ray diffraction (XRD), scanning electronic microscopy (SEM), diffuse reflectance ultraviolet‐visible spectroscopy (UV‐Vis, DRS), nitrogen adsorption at low temperature, temperature programmed desorption of ammonia (NH₃‐TPD), desorption of CO₂ (CO₂‐TPD), etc., the correlation of the catalytic performance to the structural properties of the Ag‐SiO₂‐ MgO‐Al₂O₃ catalyst was discussed in detail. This perfect catalytic performance in the direct dehydrogenation of methanol to formaldehyde without any side‐products is attributed to its unique flower‐like structure with a surface area less than 1 m²/g, and the strong interactions between neutralized support and the nano‐sized Ag particles as active centers.     

超高效液相色谱-串联质谱法对饲料中15种β-肾上腺素能激动剂的测定

动物源性食品中兽药残留是近几年来国际社会开始研究的公共卫生问题之一.世界各国加强了对国际贸易动物源性食品中兽药残留的检测,而开展饲料及饲料添加剂中兽药残留的检测是从源头进行控制的有效手段[1].     

蜂蜜中链霉素与双氢链霉素残留量的液相色谱串联质谱法测定

建立了液相色谱串联质谱（HPLC-MS/MS）同时对蜂蜜中链霉素和双氢链霉素残留量进行分析的方法。采用磷酸溶液提取,苯磺酸固相萃取柱和C18固相萃取柱串联净化,液相色谱串联质谱测定。链霉素的检出限为0.002 mg/kg,线性范围为0.005～0.100 mg/kg,相关系数为0.9992;双氢链霉素检出限为0.001mg/kg,线性范围为0.002～0.050 mg/kg,相关系数为0.9924。方法回收率为78%～95%,相对标准偏差为2.6%～4.9%。该法实用、准确、快捷,可应用于蜂蜜样品中链霉素和双氢链霉素的同时检测。     

立体选择性合成2-(a-噻吩甲酰基)-3-取代苯基-4-乙氧羰基-5-甲基-反式-2,3-二氢呋喃

溴化(a-噻吩甲酰基)甲基三苯鉮1与3-取代苯甲叉基-2,4-戊二酮 2以碳酸钾为碱,在苯中55℃条件下反应,可以较好的收率、高立体选择性地生成反-2-(a-噻吩甲酰基)-3-取代苯基-4-乙氧羰基-5-甲基-2,3-二氢呋喃3。产物结构均经波谱予以确定。本文还提出了生成产物的可能机理。     

Electrochemical and Photoelectrochemical Study of Self‐assembled Monolayer of Phytic Acid on Brass

Phytic acid is an environment-friendly reagent for processing metals. The anticorrosion and inhibiting mechanism for phytic acid monolayers self-assembled on a brass (HSn70-1) electrode has been investigated by using electrochemical and photocurrent response methods. The electrochemical measurements indicate that phytic acid is liable to form surface complexes on the brass electrode, and the self-assembled monolayers (SAM) change the structure of the electric double-layer and shift the potential of zero charge positively. The photochemical measurement indicates that the brass electrode shows a p-type photoresponse owing to the formation of a Cu2O layer on its surface, and the presence of SAM weakens significantly the photoresponse, suggesting an excellent effect on anticorrosion, which is consistent with the EIS and polarization curve measurements. Adsorption of phytic acid was found to be typical of chemisorption, which can be reasonably described on the basis of the Langmuir isotherm.