小牛胸腺脱氧核糖核酸诱导中性红聚集的机理及其影响因素

在ｐＨ７．６￣７．８和低离子强度条件下,中性红（ＮＲ）与小牛脱氧核糖核酸（ｃｔＤＮＡ）作用产生以５３５ｎｍ为特征的共振光散射增强（ＥＲＬＳ）光谱。机理研究表明,这种ＥＲＬＳ是由于ＤＮＡ诱导中性红的聚集所致。确定了最佳聚集条件,考察了聚集的影响因素。     

吩嗪染料与DNA分子相互作用的紫外-可见光谱研究

在对ＤＮＡ分子的研究中发现，一些小分子不仅可作为生物探针，还可成为以ＤＮＡ为靶目标的抗肿瘤（癌）药物的母体，如吖啶等．小分子物质与ＤＮＡ分子的非共价键力作用将改变ＤＮＡ分子构型，破坏其模板作用．本文在研究吩嗪染料——中性红（ＮｅｕｔｒａｌＲｅｄ，ＮＲ...     

DTPA－Eu~（3＋）螯合物在核酸杂交分析中的应用

报道了靶ＤＮＡ／生物素化λＤＮＡ探针／亲合素／Ｂｉｏ－ＢＳＡ（ＴＧ）－ＤＴＰＡ－Ｅｕ~（３＋）体系在核酸杂交分析中的应用。亲合素做为连结杂交体与Ｂｉｏ－ＢＳＡ－ＤＴＰＡ－Ｅｕ~（３＋）或Ｂｉｏ－ＴＧ－ＤＴＰＡ－Ｅｕ~（３＋）的桥，生物素和ＤＴＰＡ－Ｅｕ~（３＋）均标记在载体蛋白（ＢＳＡ，ＴＧ）上。优化了分析条件，比较了己二胺、乙二胺转胺化探针及载体蛋白对杂交分析的影响。方法灵敏度高（１ｐｇ／ｗｅｌｌ靶λＤＮＡ），重现性较好（ＲＳＤ＝５．７％，ｎ＝６）。     

D-氨基葡萄糖甘氨酸混配金属配合物与DNA作用的光谱研究

研究了４种Ｄ－氨基葡萄糖甘氨酸混配金属配合物的表面增强拉曼光谱（ＳＥＲＳ）,发现它们在银胶上的吸附方式基本相同,因而ＳＥＲＳ光谱相似,用电子光谱、荧光光谱、表面增强拉曼光谱研究了它们与ＤＮＡ的相互作用,发现这４种化合物与ＤＮＡ的作用能力有很大的不同,其中ＧｕＧｌｕＧ、Ｃｏ（Ⅲ）ＧｌｕＧ是值得进一步研究的可能抗癌的药物。     

D—氨基葡萄糖单配金属配合物与DNA作用的光谱研究比较

研究了５种Ｄ－氨基葡萄糖金属配合物的表面增强喇曼光谱（ＳＥＲＳ），发现它们在银胶上的吸附方式基本相同，因而有相似的ＳＥＲＳ光谱，并用ＳＥＲＳ光谱研究了它们对ＤＮＡ的作用。     

DTPA—Eu^3＋螯合物在核酸杂交分析中的应用

报道了靶ＤＮＡ／生物素化λＤＮＡ探针／亲合素／Ｂｉｏ－ＢＳＡ（ＴＧ－Ｅｕ＾３＋体在核酸杂交分析中的应用，亲合素做为连结杂交体与ｉｏ－ＢＳＡ－ＤＴＰＡ－Ｅｕ＾３＋的桥，生物素和ＤＴＰＡ－Ｅｕ＾３＋均标记在载体蛋白（ＢＳＡ，ＴＧ）上，优化了分析条件，比较了己二胺，乙二胺转胺化探针及载体蛋白对杂交分析的影响，方法灵敏度高，重现性较好（ＲＳＤ－５．７％，ｎ＝６）。     

DNA探针在羧基聚苯乙烯微珠表面的微阵列研究

报道在１－乙基－３－３－（３－二甲基氨丙基）－碳化二亚胺（ＥＤＣ）偶链剂存在下,５’－ＮＨ_２单末端和５’－Ｔｅｘ／３’－ＮＨ_２双末端修饰ＤＮＡ探针在１０μｍ 羧基功能微珠表面的微阵列特性．研究表明,ＤＮＡ探针在微珠表面的微阵列能力决定于溶液介质的ｐＨ,ＤＮＡ探针浓度和微珠总表面积．优化条件下, ２０ ｍｅｒ单链ＤＮＡ探针在微珠表面微阵列的最小分子间距约为１４ ｎｍ,而２０ ｍｅｒ双链ＤＮＡ分子微阵列的最小分子间距约为２７ ｎｍ．如果ＤＮＡ探针序列长度由 ２０增加到 ３５ ｍｅｒ,探针在微珠表面的微阵列密度降低．机理研究表明,ＤＮＡ探针在羧基功能微珠表面的微阵列方式是探针分子近平行于微珠表面．     

荧光能量转移体系在生化分析中的应用-吖啶橙(AO)-中性红(NR)荧光探针测定DNA研究

本文简述了以荧光能量转移体系测定ＤＮＡ方法的发展过程,对近几年这一领域的新成果作了介绍;同时对吖啶橙（ＡＯ）－中性红ＮＲ为荧光探针测定ＤＮＡ的条件进行分析,证明了该法具有灵敏度高、线性范围宽、检出限低、选择性好、抗干扰能力强等,该法为微量ＤＮＡ定量分析提供了一个新的途径。     

HBVDNA与抗HBcIgM在临床检测中的价值

采用地高辛标记探针以分子杂交的方法对８５１例血清进行ＨＢＶＤＮＡ的检测,采用ＥＬＩＳＡ的方法对相同标本检测了抗－ＨＢｃＩｇＭ、ＨＢＶ二对半、抗－ＨＡＶＩｇＭ、抗－ＨＣＶ及抗－ＨＥＶＩｇＭ,发现ＨＢＶＤＮＡ阳性检出率与ＨＢｅＡｇ出现相关,且ＨＢｅＡｇ阴性的标本中仍有１０．２５％（４９／４７８）ＨＢＶＤＮＡ阳性,说明仅以ＨＢｅＡｇ出现与否判定是否存在ＨＢＶ的复制是不可靠的。同时,还发现ＨＢＶＤＮＡ的出现与肝炎类型无关。抗－ＨＢｃＩｇＭ阳性率则与ＨＢｅＡｇ的出现无关,而与肝炎类型相关。     

单链脱氧核糖核酸探针在羧基聚苯乙烯小珠表面的微阵列条件及固—液杂交特

优化在１－乙基－３－（３－二甲基氨丙基）－碳化二亚胺（ＥＤＣ）存在下,５′－ＮＨ２单末端和５′－ＴＲ／３′－ＮＨ２双末端修饰单链脱氧核糖核酸（ＤＮＡ）探针在１０μｍ羧基聚苯乙烯小珠表面进行微阵列的条件,研究５′－ＮＨ２单末端修饰ＤＮＡ探针与其碱基互补充阢进行的固－液杂交特性。结果表明,在ＰＨ４．６－５．６,ＥＤＣ浓度为０．５－０．７ｇ／Ｌ时,ＤＮＡ探针在小珠表面具有最大的微阵列能力。微阵列在小珠表面的５′－ＨＮ２单末端修饰ＤＮＡ探针,与期 碱基互补序列的杂交反应遵守二级反应动力学,杂交优化条件除取决于溶液介质的ＰＨ值,离子强度和碱基互补序列 溶液介质中的浓度外,还取决于环境温度和杂交时间。测定了２５℃下微阵列在小珠表面的２０－ｍｅｒＤＮＡ探针与其溶液中互补序列的杂交反应常数。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.