A Facile Total Synthesis of 2-Geranyl-2',3,4',4-tetrahydroxydihydrochalcone with Highly 5-Lipoxygenase Inhibiting Activity

２－Ｇｅｒａｎｙｌ－２,３,４,４－ｔｅｔｒａｈｙｄｒｏｘｙｄｉｈｙｄｒｏｃｈａｌｃｏｎｅ（１,ＡＣ－５－１）,ｏｎｅｏｆａｆｅｗｎａｔｕｒａｌｏｃｕｒｉｎｇＣ－ｇｅｒａｎｙｌａｔｅｄｃｈａｌｃｏｎｅｓｉｎｎａｔｕｒｅ［１］,ｗａｓｉｓｏｌａｔｅ...     

A Simple Access to Chalcones via Modified Mukaiyama Aldol Condensation Promoted by SmI_3/TMSCl

Ｃｈａｌｃｏｎｅｓａｎｄｔｈｅｉｒｄｅｒｉｖａｔｉｖｅｓａｒｅｉｍｐｏｒｔａｎｔｉｎｔｅｒ ｍｅｄｉａｔｅｓｉｎｏｒｇａｎｉｃｓｙｎｔｈｅｓｉｓ .Ｔｈｅｙｃａｎｕｎｄｅｒｇｏｍａｎｙｋｉｎｄｓｏｆｒｅａｃｔｉｏｎｓ ,ｔｈｒｏｕｇｈｗｈｉｃｈａｗｉｄｅｒａｎｇｅｏｆｕｓｅｆｕｌｃｏｍｐｏｕｎｄｓｈａｖｅｂｅｅｎｐｒｅｐａｒｅｄ .1Ｉｎａｄｄｉｔｉｏｎ ,ｍａｎｙｃｈａｌｃｏｎｅｄｅｒｉｖａｔｉｖｅｓｄｉｓｐｌａｙｉｎｔｅｒｅｓｔｉｎｇｐｈａｒｍａｃｏｌｏｇｉｃａｌａｎｄｂｉｏｌｏｇｉｃａｌａｃｔｉｖｉ…     

微环境条件影响的光化学反应研究进展

对近年来微环境条件影响的光反应化学反应研究和一综合评述，包括主体－客体络合物，晶格控制物Ｌｅｗｉｓ酸络合物，电荷转移络合物，胶束以及吸附在硅胶或分子筛表面等体系光化学反应方面取得的重要成果，这类微环境条件影响的光化学反应具有较高的选择性和专一性，参考文献１５篇。     

Electron－rich Polynuclear Transition Metal Clusters：Ⅰ． The Clusters with Chalcogen Bridges and Phosphine Ligands

Ｅｌｅｃｔｒｏｎ－ｒｉｃｈＰｏｌｙｎｕｃｌｅａｒＴｒａｎｓｉｔｉｏｎＭｅｔａｌＣｌｕｓｔｅｒｓ：Ⅰ．ＴｈｅＣｌｕｓｔｅｒｓｗｉｔｈＣｈａｌｃｏｇｅｎＢｒｉｄｇｅｓａｎｄＰｈｏｓｐｈｉｎｅＬｉｇａｎｄｓＨｏｎｇＭａｏ－Ｃｈｕｎ；ＪｉａｎｇＦｅｉ－Ｌｏｎ...     

掺杂元素的Lewis酸强度对掺杂In2O3电性质的影响

掺杂元素的Ｌｅｗｉｓ酸强度对掺杂Ｉｎ_２Ｏ_３电性质的影响文世杰Ｇ．Ｃａｍｐｅｔ（ＬａｗｒｅｎｃｅＢｅｒｋｅｌｅｙＬａｂｏｒａｔｏｒｙ，ＢｅｒｋｅｌｅｙＣＡ９４７２０，ＵＳＡ）（ＬａｂｏｒａｔｏｉｒｅｄｅＣｈｅｍｉｅｄｕＳｏｌｉｄｅｄｕＣＮＲＳ，Ｕｎｉ...     

Benzoylation of Toluene over Al-promoted SO_4~(2-)/M_xO_y(M=Zr,Ti,Fe) Catalysts

ＴｈｅｂｅｎｚｏｙｌａｔｉｏｎｏｆｔｏｌｕｅｎｅｗｉｔｈｂｅｎｚｏｙｌｃｈｌｏｒｉｄｅｉｓａｎｉｍｐｏｒｔａｎｔａｃｉｄｃａｔａｌｙｔｉｃＦｒｉｅｄａｌＣｒａｆｔｓｒｅａｃｔｉｏｎ．Ｌｅｗｉｓａｃｉｄｓ,ｓｕｃｈａｓｄｅｈｙｄｒａｔｅｄＡｌＣｌ３ａｎ...     

α－蒎烯选择性二聚合及低聚反应研究 Ⅰ．不同催化剂体系的聚合行为和产物构成

从聚合动力学、异构化和产物构成等方面检讨了质子酸、Ｌｅｗｉｓ酸和质子酸／Ｌｅｗｉｓ酸复合酸三类，多种催化剂和各种反应条件对α－蒎烯的二聚合及低聚反应的影响，结果表明，活性种为质子Ｈ＾＋的这三类催化剂主要生成二、三、四聚体产物，发现质子酸与Ｌｅｉｗｓ酸组成的复合催化剂比单独时聚合活性大幅度提高，异构化作用显著减少，可以高选择性地合成二聚体，如复合催化剂ＡｌＣｌ３／ＣＦ３ＣＯＯＨ异构化率仅０．５％；聚     

α-氯代乙苯/TiCl4/Ti(OiPr)4引发β-蒎烯活性阳离子聚合

－４０℃条件下,在ＣＨ２Ｃｌ２溶剂中以α－氯代乙苯为引发剂,ＴｉＣｌ４和Ｔｉ（ＯｉＰｒ）４混合物为Ｌｅｗｉｓ酸活化剂,进行β－蒎烯阳离子聚合,单独使用强的Ｌｅｗｉｓ酸ＴｉＣｌ４时,聚合反应在瞬间完成,聚合产物的分子量分布较宽,添加本身无催化活性的弱Ｌｅｗｉｓ酸Ｔｉ（ＯｉＰｒ）４后,聚合反应减缓且聚合产物的分子量的分布变窄,当Ｔｉ（ＯｉＰｒ）４／ＴｉＣｌ４摩尔比为１／３时,产物的分子量随单体转化率线性增加,且分子量分布较窄,显示出活性聚合特性这种活性聚合特性由单体添加实验进一步得到证实。     

ab Initio Calculation on Tautomerism of Pyrazolin—5—ones

ａｂＩｎｉｔｉｏＣａｌｃｕｌａｔｉｏｎｏｎＴａｕｔｏｍｅｒｉｓｍｏｆＰｙｒａｚｏｌｉｎ－５－ｏｎｅｓ￥ＳｕｎＲｅｎ－Ａｎ；ＷａｎｇＣｈａｎｇ－Ｓｈｅｎｇ；ＹａｎｇＺｈｏｎｇ－Ｚｈｉ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＬｉａｏｎｉｎｇＮｏｒｍ...     

硅胶固载化—Lewis酸催化剂的研究：2.硅胶固载化—三氯化铁（FeCl3）或…

以硅胶为基质用γ－ＧＯＰＳ偶联后，接枝邻位氨基吡啶，间位，对拉酰氨基吡啶三种配体后与ＦｅＣｌ３或ＳｎＣｌ４饱和溶液络合，合成固载化的Ｌｅｗｉｓ酸催化剂，并以此类催化剂进行缩醛缩酮及酯化反应，获得良好效果。     

Utilization of Supercritical Carbon Dioxide for the Preparation of 3-Hydroxyflavone and β-Cyclodextrin Complex

The solubility of 3-hydroxyflavone in water can be enhanced by forming complex with β-cyclodextrin (β-CD). In this study we introduced supercritical carbon dioxide as a substitute solvent to prepare 3-hydroxyflavone-β-cyclodextrin complex. The maximum drug loading determined by UV spectroscopy in complex was 14.7 wt.%, which was comparable to that of 1:1 complex (17.34 wt.% of 3-hydroxyflavone). The solubility of the drug loaded in the complex was better than that of pure drug in water. The enhanced solubility was attributed to the formation of the complex and the solubility of the β-cyclodextrin in water.     

壳聚糖维生素C复合物的合成及性能

通过离子间静电引力作用合成了壳聚糖维生素C复合物。采用红外光谱和差热分析测试技术表征了复合物的结构。溶解度测定结果表明,该复合物具有水溶性。邻苯三酚自氧化速率测定结果表明,该复合物对.O2-的清除作用优于壳聚糖。     

Radical Polymerization of Maleic Acid by Potassium Persulfate in the Presence of Polyvinylpyrrolidone in Water

Maleic acid(MA) was found to polymerize easily by potassium persulfate (KPS) in water in the presence of polyvinylpyrrolidone (PVP), and to form a polymer complex in which the molar ratio of MA to VP monomer unit was approximately unity. The formation of the polymer complex was accelerated by increases in the reaction temperature, in the concentrations of KPS and MA, and in the molecular weight of PVP used. Thermal degradation behavior of the polymer complex was studied thermo-gravimetrically. The thermagram of the polymer complex was substantially different from those of PVP and the 1:1 mixture of MA and PVP. It was found that the poly-MA portion of the polymer complex decomposed at 100-300°C, while the PVP portion underwent degradation at 350-500°C. In order to separate poly-MA from the polymer complex, the polymer complex was methylated by diazomethane, and 50 ～ 60% of the poly-MA part in the polymer complex was separated as its methyl ester, which was found to be oligomer (M = 400 ～ 500) by GPC. Unseparated part of poly-MA seems to be grafted onto PVP. The polymerization of citraconic acid (CA) was also performed in the same manner. Similar results were obtained, though the polymerization of CA was slower as compared with that of MA.     

Evaluation of 99mTc-HIDA complex as a cholescintigraphic agent (author's transl)

In the reaction labeling N-(2,6-dimethylphenylcarbamoylmethyl) iminodiacetic acid (HIDA) with 99mTc, several complexes with different chemical characteristics were observed to occur with slight changes in the labeling conditions. Among these complexes, a complex detected in the bile of rats was limited to one complex, named as complex II. The preparation method of 99mTc-HIDA complex II and the exchange reaction between this complex and penicillamine indicate that 99mTc is coordinated with HIDA as low-hydrolyzed 99mTc in this complex. This complex is excreted rapidly through the bile and within 1 hr, about 65% of the total activity injected is recovered from bile in rats. The organ distribution of this complex was studied in mice by radioassay and in rabbits by scintillation camera and, in both cases, the radioactivity was accumulated in the gallbladder. These results suggest that the 99mTc chemical state, low-hydrolyzed state, relates to the bile excretion behavior of this complex, a potentially useful cholescintigraphic agent.     

Comparison of magnetic properties of DNA-cetyltrimethyl ammonium complex with those of natural DNA

We prepared the DNA-cetyltrimethyl ammonium complex, as well as the same complex intercalated with stable organic free radicals, and studied their magnetic properties by electron magnetic resonance (EMR) spectroscopy and by measuring the magnetization on a superconducting quantum interference device (SQUID). The UV-vis and CD spectra of DNA-quaternary alkyl ammonium complex (DNA--Q+) in organic solvent clearly demonstrated that it retained the double helical B-form conformation. The interhelical spacing of double strand DNA (dsDNA) increased when the counter ions (Na+) of phosphate groups of the natural DNA were replaced with the long alkyl quaternary ammonium groups. The inter-helical distance of DNA-cetyltrimethyl ammonium (CTMA) was 39.1  as confirmed by X-ray diffractometry. In general, the magnetization of the DNA-CTMA complex solid was found to be significantly lower than that of natural DNA. Moreover, intercalation of the complex with stable organic free radicals did not improve magnetization, which again was in marked contrast to natural DNA. EMR spectroscopic behavior of the complex in the solid state also was quite different from that of natural DNA: The unique broad EMR signal of natural DNA in the low field region with g-value greater than 10 disappeared in the DNA-CTMA complex.     

Integration of a microextraction system solvent extraction of a Co-2-nitroso-5-dimethylaminophenol complex on a microchip

A newly designed microchannel for solvent extraction was fabricated in a quartz glass chip and applied to solvent extraction of a Co-2-nitroso-5-dimethylaminophenol complex. The aqueous solution of Co complex and toluene were introduced into the microchannel, and the Co complex extracted in toluene was detected by thermal lens microscopy (TLM). The Co complex was quickly extracted into toluene when the flow was stopped. The observed extraction time, ca. 50 s, was almost equivalent to the value calculated using the diffusion distance and diffusion coefficient. The dependence of the TLM signal on the concentration of the Co complex showed good linearity in the range of 1 x 10(-7) - 1 x 10(-6) M.     

Asymmetric Dihydroxylation of Allylamine Catalyzed by Wool-OsO4 Complex

A new chiral polymer-metal complex, wool-osmium tetroxide(wool-OsO4) complex was prepared by a very simple method. This complex was found to be able to catalyze the asymmetric dihydroxylation of allylamine to get (R)-( )-3-amino-1, 2-propanediol. The experimental results showed that OsO4 content in the complex, reaction time, allylamine/OsO4 molar ratio all have great effects on the chemical and optical yields of product. Additionally, wool-OsO4 complex catalyst could be reused without remarkable change in optical catalytic activity.     

Stereoselective synthesis of atropisomeric korupensamines A and B utilizing planar chiral arene chromium complex

Naphthyl tetrahydroisoquinoline alkaloids, atropisomeric korupensamines A and B and ent-korupensamine B, were synthesized by syn-selective cross-coupling of a planar chiral arene chromium complex with naphthylboronic acid and subsequent axial isomerization or tricarbonylchromium migration to the inverted arene face as a key step. Palladium(0)-catalyzed cross-coupling of planar chiral arene chromium complex 12 with naphthylboronic acid 9 gave syn-biaryl coupling product 13. syn-Biaryl chromium complex 13 was heated in 1:1 mixture of di-n-butyl ether and 1,2-dichloroethane to give a face-inverted anti-biaryl chromium complex 14 without axial isomerization. Korupensamine A was synthesized from the syn-biaryl chromium complex 13 via o-formyl syn-biaryl chromium complex 10, and ent-korupensamine B was prepared from the face-inverted anti-biaryl chromium complex 14. On the other hand, difluoro-substituted syn-biaryl chromium complex 40 with a formyl group afforded anti-biaryl chromium complex 41 containing a rotated central bond by heating in xylene. The chromium-complexed fluorine atom was easily substituted with an isopropoxy group by nucleophilic substitution. Use of these reactions allowed (+)-2-bromo-3,5-difluorobenzaldehyde chromium complex (37) as a single chiral source to be converted to atropisomeric korupensamines A and B, respectively.     

The effect of the antioxidant spermine on the photophysical reactions of tryptophan in aqueous solution at 77 K

Fluorescence, phosphorescence and electron paramagnetic resonance techniques were used to investigate the effect of the antioxidant spermine on the initial photophysical reactions of tryptophan (Trp) in aqueous salt solutions at 77 K. At low concentrations of Trp (3.5 X 10(-5) M) a ground state complex was formed between one Trp and two spermine molecules (a 1:2 complex). Complexed Trp was photodegraded at a rate 65% lower than the free molecule due to a change in the charge-transfer character of the excited 1La state. At high concentrations of Trp (3.5 X 10(-3) M) the phosphorescence was almost completely quenched due to hydrogen-bond formation between two neighbouring Trp molecules. A strong complex was formed between this Trp dimer and one spermine molecule on addition of spermine (a 2:1 complex). Spermine enhanced intersystem crossing in one of the two Trp molecules in the 2:1 complex and phosphorescence was observed. From this triplet state the tryptophyl radical was formed with high efficiency by hydrogen-atom transfer. The yield of radical formation from the triplet state in the 2:1 complex was much larger than from the excited singlet state in the 1:2 complex.     

Studies on the radiolysis of U(VI)-thoron complex

This work is an investigation of the radiation stability of thoron-uranium complex. It deals mainly with the effect of absorbed dose on the absorption spectra of the complex at different complex concentrations. The radiolysis of the complex, was also investigated in presence of varying concentrations of ethanol and methanol. The decrease in absorbance at the characteristic peak as a function of absorbed dose, complex concentration, and alcohol concentration was used to calculate the G-value and the specific rate of bimolecular interaction of the complex molecule with water radiolysis products. The radiolysis mechanism was discussed in the light of the results.National Center of Radiation Research and Technology.