硒半胱氨酸和硒胱氨酸的间接气相色谱测定──溴化氰－气相色谱法

 将硒半胱氨酸（ＳｅＣｙｓＨ）甲基化，对硒胱氨酸（ＳｅＣｙｓ）需还原后再甲基化。它们生成的甲基硒半胱氨酸（ＣＨ＿３ＳｅＣｙｓＨ）能与溴化氰（ＣＮＢｒ）发生专一性反应，定量生成的硒氰酸甲酯（ＣＨ＿３ＳｅＮ）可用气相色谱法（ＧＣ）测定。此法简称ＣＮＢｒ－ＧＣ法，检测限４×１０￣（－８）克ＳｅＣｙｓ，准确度８９．５％，相对标准差１２．１％，非含硒氨基酸不干扰。此法适于样品中微量硒氨基酸（硒蛋氨酸ＳｅＭｅｔ，ＳｅＣｙｓＨ和Ｓｅｃｙｓ）的测定。     

硒酵母中有机硒及硒代氨基酸含量的测定方法

报道了人工培养硒酵母中有机硒及硒代胱氨酸（ＳｅＣｙｓ）和硒代蛋氨酸（ＳｅＭｅｔ）含量的测定方法。采用透析处理法使硒酵母中的无机硒和有机硒得以分离,并采用催化分光光度法测定了硒酵母中有机硒的含量;采用氨基酸自动分析仪测定了硒酵母中ＳｅＣｙｓ和ＳｅＭｅｔ的含量。     

化合物Cs3Dy2Br9合成机理的相化学研究

研究了ＣｓＢｒ与ＤｙＢｒ３在氢溴酸介质中反应的四元体系ＣｓＢｒ－ＤｙＢｒ３－ＨＢｒ（１３％）－Ｈ２Ｏ（２５℃）相化学关系，发现了新物相５：３型化合物５ＣｓＢｒ．３ＤｙＢｒ．２４Ｈ２Ｏ，并对其进行了Ｘ射线，ＤＴＧ，ＤＴＡ及偏光显镜等方面的研究。     

硒(Ⅳ)-四乙基碘化铵-砷(Ⅲ)体系的极谱吸附波及其应用

报道了一个测定硒的高灵敏极谱吸附波新体系。在 ０． ７ ｍｏｌ／Ｌ ＨＢｒ溶液中，Ｓｅ（Ⅳ）－ （Ｃ２Ｈ５）４ＮＩ－Ａｓ（Ⅲ）体系于－０．６１Ｖ（ｖｓ．ＳＣＥ）处产生一高灵敏的极谱吸附波。峰电流与Ｓｅ （ Ⅳ）浓度在 ０． １～４０ μｇ／Ｌ范围内呈线性关系。检出限为 ０． ０５ μｇ／Ｌ。研究了极谱波的性质。 用本法测定了土壤中的全硒和有效硒，结果满意。     

硒保护离体培养人肝细胞膜流动性的机制探讨

原代培养人胚细胞经不同剂量硒预保护后，用四氯化碳（ＣＣｌ４）攻击，观察细胞膜流动性及培养液中谷胱甘肽过氧化物酶（Ｓｅ－ＧＳＨ－Ｐｘ）与两二醛（ＭＤＡ）比值的变化．结果；与正常对照组比较，ＣＣｌ４损伤组肝细胞膜流动性明显降低，差异有显著性意义（Ｐ＜０．００１）。与ＣＣｌ４．损伤组比较，硒保护组股流动性显著增大．同时，Ｓｅ－ＧＳＨ－Ｐｘ活性明显提高，ＭＤＡ产生量显著减少，差异均有显著性意义（Ｐ＜０．０１）。且细胞膜流动性与Ｓｅ－ＧＳＨ－Ｐｘ／ＭＤＡ比值呈显著正相关（ｒ＝＋０．９４７３，Ｐ＜０．０１）。因此，本文认为硒可以提高Ｓｅ－ＧＳＨ－Ｐｘ／ＭＤＡ比值，增强细胞抗氧化能力，维护人肝细胞膜流动性．     

硒（IV）—四乙基碘化铵—砷（Ⅲ）体系的极谱吸附波及其应用

报道了一个测定硒的高灵敏极谱吸附波新体系。在０．７ｍｏｌ／Ｌ ＨＢｒ溶液中，Ｓｅ（Ⅳ）－（Ｃ２Ｈ５）４ＮＩ－Ａｓ（Ⅲ）体系于－０．６１Ｖ（ｖｓ．ＳＣＥ）处产生一高灵敏的极谱吸附波。峰电流与Ｓｅ（Ⅳ）浓度在０．１￣４０μｇ／Ｌ范围内呈线性关系。检出限为０．０５μｇ／Ｌ。研究了极谱波的性质。用本法测定了土壤中的全硒和有效硒，结果满意。     

含杂环卡宾碳的铁羰基簇合物的结构化学研究Ⅱ．—Fe_3(CO)_8[:CNHC(S)C(CH_3)_2NH]的合成和晶体结构

Ｆｅ３（ＣＯ）＿（１２）和取代２，４＿二硫代乙内酰脲反应，得到新的取代物Ｆｅ３（ＣＯ）＿８－［：ＣＮＨＣ（Ｓ）Ｃ（ＣＨ＿３）＿２ＮＨ］（μ＿３－Ｓ）＿２，并进行了ＩＲ、１￣ＨＮＭＲ、ＭＳ表征，测定了它的分子和晶体结构，讨论了杂环卡宾碎片：ＣＮＨＣ（Ｓ）Ｃ（ＣＨ＿３）＿２ＮＨ的取代位置，它是通过卡宾碳原子与Ｆｅ配位。     

Syntheses，Structures and Properties of Some New Composition Perovskite Compounds：Sr_（0．6）Bi_（0．4）FeO_（2．7），Sr_（1－x）Bi_xFeO_（3－y） and Ba_（1．5）Pt_（0．5）Mn_2O_6

Ｓｙｎｔｈｅｓｅｓ，ＳｔｒｕｃｔｕｒｅｓａｎｄＰｒｏｐｅｒｔｉｅｓｏｆＳｏｍｅ　ＮｅｗＣｏｍｐｏｓｉｔｉｏｎＰｅｒｏｖｓｋｉｔｅＣｏｍｐｏｕｎｄｓ：Ｓｒ_（０．６）Ｂｉ_（０．４）ＦｅＯ_（２．７），Ｓｒ_（１－ｘ）Ｂｉ_ｘＦｅＯ_（３－ｙ）　ａｎｄ　Ｂａ...     

硒－硫氰酸钾－罗丹明B－明胶－OP体系分光光度法测定微量硒

硒的分光光度法一般采用硒试剂作显色剂，其灵敏度低，操作繁琐。硒－硫氰酸盐－丁基罗丹明Ｂ－吐温－２０体系分光光度法测定微量硒的灵敏度较高￣［１］，在该文的基础上，本人研究出硒－硫氰酸钾－罗丹明Ｂ－明胶－ＯＰ体系分光光度法，具有灵敏度高，稳定性好，操作简便等特点。研究结果表明：在明胶－乳化剂ＯＰ存在下，控制溶液ｐＨ３．８，用硫脉作还原剂，ＥＤＴＡ为掩蔽剂，硒与硫氰酸钾及罗丹明Ｂ生成三元配合物，配合比Ｓｅ（Ⅳ）：ＣＮＳ￣－：ＲＢ＝１：６：４，最大吸收波长为６０６ｎｍ，硒含量在０～３μｇ／２５ｍＬ服从比尔定律，ε＿（６０６）＝７．９×１０￣５Ｌ．ｍｏｌ￣（－１）·ｃｍ￣（－１）。用于矿泉水中微量硒的测定。     

三羰基环戊二烯基钼负离子与1，3－二卤丙烷的反应

三羰基环戊二烯基钼负离子与１，３－二卤丙烷在一缩二乙二醇二甲醚介质中反应，生成环卡宾配合物ＣｐＭｏＸ（ＣＯ）＿２ＣＯ（ＣＨ＿２）＿２ＣＨ２（Ｘ＝Ｂｒ，Ｉ）．硅桥连双环戊二烯基三羰基钼负离子与１，３－二卤丙烷顺利地进行类似反应，生成相应的硅桥连双［环卡宾钼配合物］──Ｅ［Ｃ＿５Ｈ＿４ＭｏＸ（ＣＯ）＿２］ＣＯ（ＣＨ＿２）＿２ＣＨ＿２］＿２（Ｅ＝Ｍｅ＿２Ｓｉ，Ｍｅ２ＳｉＳｉＭｅ＿２，Ｍｅ２ＳｉＯＳｉＭｅ＿２）．化合物硅氧硅桥联二茂二钼环卡宾配合物１１的晶体结构经Ｘ射线衍射测定，晶体属三斜晶系，Ｐ１空间群，晶体学数据：ａ＝０．８１８８（１）ｎｍ，ｂ＝１．０４５（３）ｎｍ，ｃ＝２．３２５２（４）ｎｍ，α＝９４．１４（２）°，β＝９４．０９（１）°，γ＝１０２．４８（２）°，Ｖ＝１．９３０６ｎｍ￣３，Ｚ＝２，Ｄ＿ｃ＝１．８５４ｇ／ｃｍ￣３。     

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%.     

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

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.     

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.     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.