中国化学快报

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Cyclopropanation of Diazoacetate with Olefins

Zheng Ning LI, Hui Lin CHEN

中国化学快报. 1996, 7(09): 785-787.

摘要 ( )

可视化

Nine copper compounds are used for catalyzing the cyclopropanation of l-hexene/TME with alkyl diazoacetate. Cu (Salad) ₂ shows the highest yield for the reaction of TME at high temperature such as 100℃. The reaction of crude RDA with TME in 73.7% yield under the optimal condition is obtained.

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Selective Reduction of α,β-Unsaturated Amides with NaBH₄/BiCl₃ System

Ping Da REN, Shi Feng PAN, Ting Wei DONG, Shi Hui WU

中国化学快报. 1996, 7(09): 788-789.

摘要 ( )

可视化

α, β-Unsaturated amides with various substitution patterns at the carbon-carbon double bond and nitrogen atom can be reduced to the corresponding saturated amides with high selectivity and yields with NaBH₄/BiCl₃ system.

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Oxidative Coupling of Phenols by 2,2,6,6-Tetramethyl-4-methoxypiperidine Oxoammonium Chloride

You Cheng LIU, Wei WANG, Qing Xiang GUO

中国化学快报. 1996, 7(09): 790-793.

摘要 ( )

可视化

The reactions of several phenols with 2, 2, 6, 6-tetramethyl-4-methoxypi-peridine oxoammonium chloride were studied. It was found that this oxoammonium salt is a facile reagent for the oxidative coupling of phenols, o-substituted phenols gave the para-para-coupling products and p-substituted phenols gave the ortho-ortho-coupling products, while o-, p-substituted phenol gave the corresponding dehydrogenated coupling product.

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Photosensitized Cycloreversion of Cage Compound via Triplet Energy Transfer

Chen Ho TUNG, Yun Ming YING

中国化学快报. 1996, 7(09): 794-796.

摘要 ( )

可视化

Several triplet sensitizers were found to be able to photosensitize cycloreversion of the photodimer (1) of methyl naphthalene-2-carboxylate. With the increase of the donor's triplet energy, the quantum yield of the isomerization is increased. The cycloreversion mechanism of 1 was suggested to proceed via triplet energy transfer.

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Studies on Organophosphorus Compounds 97.Cu₂O-catalyzed Reaction of Isocyanoacetate with 1-Oxoalkylphosphonate.A Novel Stereoselective Synthesis of β-Phosphoryl α,β-Dehydroamino Acid Derivatives

Wei Sheng HUANG, Yi Xin ZHANG, Cheng Ye YUAN

中国化学快报. 1996, 7(09): 797-798.

摘要 ( )

可视化

Cu₂O-Catalyzed reaction of isocyanoacetate with l-oxoalkylphosphonatrs afforded predominantly Z-α-formylamino-β-phosphoryl-α, β-alkenoate.

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1,2-Cyclic Monoalkly-rac-Glycerothiophosphates of 2',3'-O-Isopropylideneuridine

Huan Ming CHEN, Ru Yu CHEN, Ping Ying LI, Cheng Xiang ZHANG

中国化学快报. 1996, 7(09): 799-800.

摘要 ( )

可视化

A series of 1, 2-cyclic monoalkyl-rac-glycerothiophosphates of 2', 3'-O-isopropylideneuridine were synthesized in a one-pot procedure in overall yields of 36-40% by means of hexaethylphosphorous triamide as phosphorylating reagent.

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Synthesis of (±)-Deoxyschisandrin and the Corresponding Trans-lsomer

Jun Biao CHANG, Jing Xi XIE

中国化学快报. 1996, 7(09): 801-802.

摘要 ( )

可视化

(±)-Deoxyschisandrin 1 and the corresponding trans-isomer 2 were readily prepared by intramolecular oxidative coupling of 1.4-diaryl-2.3-dimethylbutanes 7 and 6 with 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone (DDQ) in trifluoroacetic acid (TFA).

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Synthesis of an N⁵N¹⁰-methenyltetrahydrofolate Model and Its Substituted One-Carbon Unit Transfer Reaction

Jian Xin CHEN, Chi Zhong XIA, Jin Pei CHENG

中国化学快报. 1996, 7(09): 803-806.

摘要 ( )

可视化

Substituted imidazolinium salt, l, 2-dimethyl-3-(p-methoxybenzenesulfonyl) imidazolinium iodide, as a tetrahydrofolate model in terms of the ability to transfer a substituted one-carbon unit (ethylidyne, nitromethylethylidene), can react with a variety of mono- and bifunctional nucleophiles and lead to some carboline alkaloids and other heterocyclic compounds.

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Synthesis and Amphiphilic Characteristics of 8-Hydroxyquinoline with Alkyl Chain

Jian Ming OUYANG, Chao Yang JIANG, Zi Hou TAI, Wen Xia TANG

中国化学快报. 1996, 7(09): 807-808.

摘要 ( )

可视化

The amphiphilic derivatives of 8-hydroquinoline with alkyl chain have been synthesized. These derivatives can form stable monolayer on pure water and an aqueous subphase containing metal ions.

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De Novo Design and Synthesis of Four-Helix Bundle Peptides

Xiang Qun LI, Zhen Wei MIAO, Yu LUO, Cong Xi LI, You Qi TANG

中国化学快报. 1996, 7(09): 809-811.

摘要 ( )

可视化

Two peptides (LI22 and LI29) designed to form four-helix bundle were synthesized by stepwise solid phase peptide synthesis (SPPS) using Fmoc strategy, purified by reversed phase high performance liquid chromatography (HPLC) and confirmed by fast atom bombardment mass spectrum (FABMS).

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Three Heptad Repeats Are Long Enough to Form Highly Stable α-Helix Structure

Xiang Qun LI, Zhen Wei MIAO, Yu LUO, Xiao Jie XU, You Qi TANG

中国化学快报. 1996, 7(09): 812-815.

摘要 ( )

可视化

As an attempt to find out how the sequence length determine the α-helix formation, seven peptides containing 2 to 4 heptad repeats (16-29 residues long) were designed and characterized. Results of circular dichroism (CD) show that two-heptad repeats are not long enough to form highly helical structure, while more than three are adequate, in aqueous solution.

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Structures of Isodoternifolin A and B

Zhi Min WANG, Hao FENG, Xiao Tian LIANG

中国化学快报. 1996, 7(09): 816-817.

摘要 ( )

可视化

Two new diterpenoids, named isodoternifolins A (1) and B (2), together with seven known compounds were isolated from the ethanol extract of dried stems and leaves of Isodon temifolius (D. Don) Kudo. The structures of 1 and 2 were determined as 7β-hydroxy-6β, 11α, 15β-triacetoxy-7α, 20-epoxy-entkaur-16-ene and 6β, 7β, 15β-trihydroxy-11α-acetoxy-7α, 20-epoxy-entkaur-16-ene by chemical and spectral evidence respectively.

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A Study on the Simultaneous Determination of Copper and Tin in the Presence of Lead

Xiao Li ZHANG, Chi Min DU

中国化学快报. 1996, 7(09): 818-819.

摘要 ( )

可视化

A very sensitive electrochemical procedure for trace determination of copper and tin in the presence of lead using cathodic adsorption voltammetry is presented. The complex of copper, tin with salicylfluorone (SAF) is adsorbed on the hanging mercury drop electrode (HMDE) and the reduction current of the accumulated complex is measured by voltammetry. This method achieves the simultaneous determination of copper and tin, and has been applied to determine canned food.

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A New Fluorescence Method for the Measurement of Intracellular Free Rare Earth Ions:Fura-2 as an Indicator

Pin YANG, Tian Xin WEI, Chun Ying, Jin Xi WANG, Da Pin FAN

中国化学快报. 1996, 7(09): 820-822.

摘要 ( )

可视化

Fura-2 was first used to monitor intracellular RE³⁺. The characterizations of RE³⁺-Fura-2 interactions in solutions simulating intracellular ionic composition show that La³⁺ and Y³⁺ both form 1:1 RE³⁺-fura-2 complexes. The apparent dissociation constants are 1.61×10^-7M, and 4.04×10^-7M, respectively. The mouse myeloma (SP2/0) cells exposed to free RE³⁺ or free RE³⁺ and some small molecules in body were studied by single cell cation measurement system. The results support the assumption that RE³⁺ ions cannot enter the cytoplasm of living cells, and the small molecules used in our experiments couldn't improve the permeability of RE³⁺ ions.

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Determination of Speciation of Magnesium (Ⅱ) in Albumen by Gel Permeation Chromatography

Ming SONG, Hui Min MA, Yue Xian HUANG, Shu Quan LIANG

中国化学快报. 1996, 7(09): 823-824.

摘要 ( )

可视化

A gel permeation chromatographic method using cross-linked dextran G-50 was employed to determine the speciation of magnesium (Ⅱ) in albumen. It has been found that 0.22% of magnesium (Ⅱ) in albumen combines with proteins and the rest exists as free ions and small-molecular complexes.

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In-situ Thin Layer Spectroelectrochemical Study of the Redox Mechanism add Intermediate for Vitamin B₂ in Aqueous Solution

Yong Jun MA, Shi Min ZHU

中国化学快报. 1996, 7(09): 825-828.

摘要 ( )

可视化

The electrochemical reaction mechanism of Vitamin B₂ on platinum electrode in acid aqueous solution has been studied by thin layer cyclic voltammetry (TLCV) and thin layer spectroelectrochemistry (TLSEC). The results indicate that there is a redox process of VB₂ via a semiquinone radical to dihydroflavin. The radical intermediate has been detected by in-situ UVSEC method for the first time.

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Study on the Application of Polysiloxane with N-decanyltartrimide Moieties in Capillary Electrophoresis

Li Feng ZHANG, Shen HU, Xue Ran LU, Jie Ke CHENG, Yuan Yin CHEN

中国化学快报. 1996, 7(09): 829-830.

摘要 ( )

可视化

Synthesis of polysiloxane with N-decanyltartrimide moieties and its application in coated capillary electrophoresis are reported.

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Investigation of Computerized Dynamic Oscillographic Analysis

Hong QI, Peng LIU, Jian Bin ZHENG

中国化学快报. 1996, 7(09): 831-834.

摘要 ( )

可视化

A high speed data sampling system on dynamic Oscillographic analysis was established with a 80386DX40 computer, AD 674 and flow injection system. Programs were designed in Microsoft Windows 3.1, that can process E-t, dE/dt-t, i'_f-t and other kinds of curve on oscillographic analysis. A satisfactory result on determination of Pb²⁺ and Cd²⁺ was obtained.

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Measurement of Concentration Distribution of Electrogenerated Etchant Using an Electrochemical Probe Technique

Lian Yong SU, Jin LUO, Zhong Hua LIN, Zhao Wu TIAN

中国化学快报. 1996, 7(09): 835-836.

摘要 ( )

可视化

An electrochemical probe measurement system for detecting an electrogenerated etchant in solution is developed. Concentration distribution of electrogenerated etchant bromine as close as 8 micrometer to the surface of macrodisk is studied quantitatively.

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A New Method for Screening Immune Drugs by Linear Sweep Polarography

Xiao Feng KANG, Liang Cheng HU, Jun Feng SONG, Yin Hua HU

中国化学快报. 1996, 7(09): 837-840.

摘要 ( )

可视化

It was found that the polarographic reduction wave of hemolysin in phosphate buffer solution was closely related to its biological activity. According to the various effects of drugs on the formation of hemolysin antibody, a new method for screening immune drugs was established.

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Zeolite-Catalyzed Friedel-Crafts Acylation of Aromatics.Ⅳ.Nature of the Active Sites of Zeolites

Yu Dao MA, Qi Long WANG, Wei JIANG, Be Jun ZUO, Qin QIU

中国化学快报. 1996, 7(09): 841-844.

摘要 ( )

可视化

For zeolite-catalyzed Friedel-Crafts acylation of aromatic rings, the Lewis acid sites were found to be active;while the Bronsted acid sites with moderate strength were found to be inactive.

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Catalytic Dechlorination of Polycyclic Chloroaromatics with Dicyclopentadienyl Yttrium Chloride Ⅱ

John H. Penn, Dao Li DENG, Chang Tao QIAN

中国化学快报. 1996, 7(09): 845-846.

摘要 ( )

可视化

Catalytic dechlorination of 1-chloronaphthalene (Ⅰ), 2-chloronaph-thalene (Ⅱ), o-chlorobiphenyl (Ⅲ), m-chlorobiphenyl (Ⅳ), p-chlorobiphenyl (Ⅴ) 1-chloroanthracene (Ⅵ) and 2-chloroanthracene (Ⅶ) has been studied with dicyclopentadienyl yttrium/NaH system. The dechlorination products for (Ⅰ), (Ⅱ), (Ⅲ), (Ⅳ) and (Ⅴ) are corresponding aromatics in excellent yields. However for (Ⅵ) and (Ⅶ), the dechlorination products are mixed aromatics.

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Carbonylation of Allyl Chloride Catalyzed by PdCl₂(TPPTS)₂ in Two-phase Medium

Heng JIANG, Yun XU, Shi Jian LIAO, Dao Rong YU, Hua CHEN, Xian Jun LI

中国化学快报. 1996, 7(09): 847-848.

摘要 ( )

可视化

PdCl₂ (TPPTS) ₂ exhibits very high catalytic activity for carbonylation of allyl chloride in aq. NaOH/toluene two-phase medium under atmospheric pressure. The average turnover frequency (TOFav, mol substrate/mol Pd·min) reaches 31 min^-1.

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Ni/Mo₂ N as a Highly Active Hydrodenitrogenation Catalyst

Wen Yu ZHANG, Xin Ping WANG, Heng Fang JIN, Qin XIN

中国化学快报. 1996, 7(09): 849-852.

摘要 ( )

可视化

The catalysts were prepared by the temperature programmed reaction (TPR) of MoO₃ with NH₃ at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ. It is shown that molybdenum nitride (Mo₂N) was formed above 923K and its intermediate MoO₂ formed at about 573~623K under the rapid (5K/min. ) TPR conditions. Mo₂N is the most active species for pyridine HDN among MoO₃, MoO₂, MoS₂, and Mo₂N. Moreover, it can be promoted by adding Ni component. It is shown that the Ni/Mo₂N catalyst prepared by adding some NiO into the precursor MoO₃ has a steady HDN activity which is far higher than that of the commercial sulfided NiMo/Al₂O₃ (HR346) catalyst.

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Dimerization Constant Determination of 6-O-Benzoyl-β-Cyclodextrin in Aqueous Solution.

Ai You HAO, Lin Hui TONG, Yao Hong FU, Xia Fei LAO, Hou Ming WU

中国化学快报. 1996, 7(09): 853-854.

摘要 ( )

可视化

Dimerization constant of 6-O-benzoyl-β-CD, which is insoluble in water, was determined for the first time by a calculation method involving an approximation step as well as a geometric step. This calculation method can be applied to other functionally modified cyclodextrin host compounds.

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The Effect of the CO(a₃П) Vibrational Population on the CO(a₃П)+NO(X₃П) Energy Transfer Reaction

Chuan Pu LIU, Xiang Yang LI, Jing Zhong GUO, Yue Shu GU, Xue Chu LI, Guan Lin SHEN, Hong CHEN

中国化学快报. 1996, 7(09): 855-858.

摘要 ( )

可视化

The improved beam sources CO (a, v≤4) and CO (a, v≤3) are produced in a beam-gas experiment by collision of CO₂ with He (2² S) and Ar (³P_{0, 2}) respectively. The energy transfer reaction of CO (a) with NO (x) mainly give NO (A, v). The vibrational distribution of CO (a) has a considerable effect on that of NO (A, v) and the vibrational distributions of NO (A, v) follow the energy gap law and the Franck-Condon (F-C) principle.

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An Oligomer Approach to Geometry Optimization for Two Dimensional Periodic Polymers

Hong You GUO, Ping WANG, Jing LI, Luke A. BURKE

中国化学快报. 1996, 7(09): 859-861.

摘要 ( )

可视化

The oligomer approach used in geometry optimization for two dimensional polymers and crystals has been developed. Geometry optimization for planar π-conjugated system, graphite, with the oligomer approach has been performed at AM1 level and the result is in good agreement with the experimental.

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The Rmodynamic Study on the Aqueous Complexation of Metal Cations with N-acetic Acid Substituted Tetraazamacrocycle

Jian Hong BI, Fu Xin XIE, Li Qin CHEN, Shi Sheng NI

中国化学快报. 1996, 7(09): 862-863.

摘要 ( )

可视化

The stability constants of the 1:1 complexes of H₄L (5.12-diphenyl-7, 14-dimethyl-1, 4, 8.11-tetraazamacroeyclotetradecane-N', N", N"', N""-tetraacetic acid) with M^2- ions (M=Cu, Ni, Co, Zn, Mn, Cd, Mg, Ca, Sr, Ba) were determined in 0.5 mol L KCl aqueous solution at 45℃, 50℃ and 60℃ by potentiometric titration and computer fitting. The △H and △S of the coordination reaction in the solution were given.

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Studies on the Protonation and Complexations of Dioxotetraamine Macrocycles

Wan Dong CHEN, Xiang Chen YIN, Shou Rong ZHU, Hua Kuan LIN, Appolin Bave KONDIANO, Mei Rong LIN, Yun Ti CHEN

中国化学快报. 1996, 7(09): 864-867.

摘要 ( )

可视化

14-Membered macrocyclic dioxotetraamines deprotonate stepwisely upon coordination to cupric ions. Singly- and doubly-deprotonated complexes are the main species. While for 13-membered analogs, non- and doubly-deprotonated complexes are the main species.

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Studies on the Immobilized Supramolecular Inclusion Complex of Iron-porphyrin as an Analogue for Peroxide Proteinase

Min ZHU, Lu Yuan MAO, Xue Mei HUANG, Rong LI, Han Xi SHEN

中国化学快报. 1996, 7(09): 868-871.

摘要 ( )

可视化

The supramolecular inclusion complex of Fe-tetrakis (sulfophenyf)-porphine (FeTPPS₄) with β-cyclodextrin (β-CD) cross-linking polymer (β-CDP) was used as an analogue for peroxide proteinase. The immobilized inclusion complex was found to exhibit high proteinase-like activity, which has been demonstrated by enzymatic methods of hydrogen peroxide.

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New Evidences for the Adsorption of Methane over Oxide Surfaces

Fa Qiang XU, Shi Kong SHEN, Jin Zhen XUE

中国化学快报. 1996, 7(09): 872-874.

摘要 ( )

可视化

It is indicative of the TSR result that CH₄ was strongly adsorbed on well degassed SrCO₃ surface at high temperature. A desorption peak of CH₄ was found in CH₄-TPD profile which appeared at ca. 310℃. The strong adsorption of CH₄ over the surface of SrCO₃ was attributed to the strong basicity of SrO sites resulted from decomposition of SrCO₃.

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Study of the Interaction between Cationic Surfactant and Polyacryldmide with Various Hydrolysis Degree

Xin Ping WANG, Ji An TANG, Long JIANG

中国化学快报. 1996, 7(09): 875-878.

摘要 ( )

可视化

BAM and π-A isotherms were used to study the interaction between cetyltrimethylammonium bromide (CTAB) and polyacrylamide with various hydrolysis degree (HPAM). Viscosity and Zeta-potential measurements were employed to investigate the properties of PAM solution. In order to explain the experimental results. we supposed that a comblike complex, which is surface active, was formed between CTAB and HPAM.

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1996年, 第7卷, 第09期　刊出日期：1996-09-20

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1996年, 第7卷, 第09期 刊出日期：1996-09-20

1996年, 第7卷, 第09期　刊出日期：1996-09-20