Reactions of regioisomeric fluoroalkyl-containing β-aminovinyl ketones with hydrazines

Fluoroalkyl -alkyl--aminovinyl ketones react with hydrazine hydrate to give the respective razoles and with phenylhydrazine they form a mixture of pyrazoles and 5 hydroxy-²-pyrazolines. Alkyl(aryl) -fluoroalkyl--aminovinylketones do not react with the hydrazines mentioned above. With 2,4-dinitrophenylhydrazine, both types of fluoroalkyl-containing -aminovinyl ketones give only hydrazones of the corresponding methyl alkyl(aryl) ketones.     

Ab initio and DFT studies on tautomerism of indazole in gaseous and aqueous phases

Electronic structure of optimized Ge₅, Ge₁₇, Ge₅–O and Ge₅ embedded in SiO₂ nanoparticles have been studied by density functional theory to find out the effect of cluster size and Ge–O bond(s) on the optical energy gap between LUMO and HOMO. It was found that the optical energy gap depends on both cluster size and the number of Ge–O bonds nonlinearly. The optical energy gap was found to be in visible light range when the Ge₅ nanoparticle has been embedded in SiO₂ matrix.     

Novel chemical modifications at the 4-position of chromones. Synthesis and reactivity of 4H-chromene-4-spiro-5′-isoxazolines and related compounds

Reactions of chromones with dilithiooximes proceed via nucleophilic 1,2-addition to give, on acidification, 4H-chromene-4-spiro-5′-isoxazoline derivatives in high yields. On treatment with concentrated H₂SO₄ the isoxazoline ring of this novel spiroannulated heterocyclic system opens to give α,β-unsaturated oximes, which undergo nitrosation, bromination, and the Beckmann rearrangement to the corresponding spiroisoxazolines and α,β-unsaturated amides, respectively. The latter can be obtained directly by the Beckmann rearrangement of 4H-chromene-4-spiro-5′-isoxazolines.     

Carboxylic Acids from <Emphasis Type="Italic">Phyllanthus urinaria</Emphasis>

Five compounds, terephthalic acid mono-[2-(4-carboxy-phenoxycarbonyl)-vinyl] ester (1), (E)-3-(5′-hydroperoxy-2,2′-dihydroxy[1,1′-biphenyl]-4-yl)-2-propenoic acid (2), 3,4,5-trihydroxybenzoic acid (3), succinic acid (or butanedioic acid) (4), and 2,3,4,5,6-pentahydroxybenzoic acid (5), were isolated from Phyllanthus urinaria. The structures of these compounds were elucidated by means of spectral techniques including IR, MS, and 1D/2D NMR. 1 and 2 are new compounds.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 14–17, January–February, 2005.     

2,4—二氨基—5—取代苄基嘧啶类质谱研究

报道了8个2,4-二氨基-5-取代苄基嘧啶衍生物的电子轰击质谱及碰撞活化解离和质量分析离子动能谱.该谱提供了化合物醚键及2,4-二氨基-5-取代苄基嘧啶环的主要碎裂途径,总结了一些裂解规律,将有助于这类化合物的结构推断。     

5-氟尿嘧啶-1-乙酸合铜(Ⅱ)的合成及其与DNA的作用

The 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) were synthesized and the date for the crystal complex was obtained. The interaction of 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) with DNA was also investigated by using spectral, viscometric, electrochemical and agarose gel electrophoresis methods. The results of interaction with DNA suggest that both 5FuAA and 5FuAACu can bind to DNA in a static electricity attraction mode. But the attraction of 5FuAACu is greater than that of 5FuAA.     

A new synthesis of trifluorinated compounds via 1,1-dichloro-1-alkenes in superacid

A two step process for converting ketone or aldehyde via 1,1-dichloro-1-alkenes to the corresponding 1,1,1-trifluoroderivatives is described, based on HF addition and chlorine-fluorine exchange under superacidic conditions.     

3-氨基环己基甲酸和cis-3-氨基环己烯基-5-甲酸立体异构体的合成

通过手性胺拆分方法，从3-环己烯基甲酸出发分别合成得到了3-氨基环己基甲酸（ACHC）的四个立体异构体，以及cis-5-氨基-3-环己烯基甲酸（ACHEC）的二个立体异构体。     

3,5-diBr-DMPAP直接光度法测定葡萄糖酸锌含量

为建立一种快速、简便、灵敏测定葡萄糖酸锌含量的方法,在非离子型表面活性剂聚氧乙烯异辛基苯基醚(TritonX-100)存在下,用2-(3,5-二溴-2-吡啶偶氮)-5-二甲氨基酚(3,5-diBr-DM-PAP)作显色剂,直接光度法测定了葡萄糖酸锌。结果表明,该法显色络合物最大吸收波长为560 nm,线性范围为0~1.5μg.mL-1,表观摩尔吸光系数为1.10×105L.mol-1.cm-1,回收率为98.7%~102.2%,具有操作快速、简便,结果灵敏可靠等优点,应用该法直接测定补锌口服液葡萄糖酸锌含量,结果满意。