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71.
氯化血红素催化新型荧光反应测定葡萄糖的研究 总被引:3,自引:0,他引:3
本文用流动注射分析了研究了过氧化物模拟酶催化过氧新型荧光底物(N,N-二氰甲基邻苯二胺,DCMOPA)的最优条件。结果表明,该系统可用于定量测定氧化氢及催化氯化血红素的浓度。 相似文献
72.
2,2-Dimethyl-3-(2-methyl-3-indolyl)cyclopropylacetic acid, its amide and esters, and the corresponding alcohol, viz., the product of ester reduction by LiAlH4, were synthesized. The chemoselectivity of N- and O-alkylation of these compounds was studied. Selective monoalkylation at the nitrogen atom of the heterocycle, O-alkylation to the side chain, or dialkylation at both nucleophilic sites can be carried out under conditions of phase-transfer catalysis. The N-acylation at the indole fragment of nitrile of this acid occurs only under the Vilsmeier—Haak formylation conditions. 相似文献
73.
We describe the first studies on the chemistry of 2-(2-oxo-3-phenylpropyl)benzaldehydes, which were converted into 3-benzylisochromen-1-ones via the corresponding 2-(2-oxo-3-phenylpropyl)benzoic acid. The 2-(2-oxo-3-phenylpropyl)benzaldehydes proved to be convenient starting materials for the synthesis of 3-phenyl-2-naphthols. Oxidation of the latter compounds resulted in a novel, efficient synthesis of 3-phenyl-1,2-naphthoquinones, which were efficiently transformed into 2-hydroxy-3-phenyl-1,4-naphthoquinones. 相似文献
74.
Bernd Schetter 《Journal of organometallic chemistry》2004,689(9):1472-1480
N,N′-dicyclohexyl-N-ferrocenoylurea 2, N,N′-diisopropyl-N-ferrocenoylurea 3, N,N′-di-p-tolyl-N-ferrocenoylurea 4 and N,N′-di-tert-butyl-N-ferrocenoylurea 5 were obtained by reaction of ferrocenecarboxylic acid 1 with N,N′-dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC), N,N′-di-p-tolylcarbodiimide 10 and N,N′-di-tert-butylcarbodiimide 11, respectively. Both N-tert-butyl-N′-ethyl-N-ferrocenoylurea 6 and N′-tert-butyl-N-ethyl-N-ferrocenoylurea 7 were obtained by reaction of 1 with N-tert-butyl-N′-ethylcarbodiimide 12. In all cases a small amount of ferrocenecarboxylic anhydride 8 was formed as a by-product. All compounds were characterized by 1H NMR, 13C NMR, IR and MS. Single crystal X-ray structural analyses were made of 2, 3 and 4. From the consistent results, the reaction products of 1 with carbodiimides appear different from those proposed by some earlier workers. With N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride 9 ferrocenoylurea was not isolated, but the main product was rather 8. The suitability of 8 as acylation reagent was applied by using 9 to obtain N-(3-triethoxysilyl)-propylferrocenecarboxamide in a one-pot reaction from 1 and 3-(triethoxysilyl)-propylamine. 相似文献
75.
α-Bromo benzolymethylene triphenylphosphorane 3 has been synthesized by the reaction of benzoylmethylene triphenylphosphorane 1 with N-bromosuccinimide in the yield of 87% and can react with aromatic aldehydes 4 to give α-bromochalcones 5 in good yields. 相似文献
76.
Ulrich Jordis 《Monatshefte für Chemie / Chemical Monthly》1986,117(11):1339-1342
5-Amino-benzo-1,3-dithiol, available by reduction of 5-amino-benzo-1,3-dithiol-2-thion, was elaborated into dithio-oxolinic Acid (6 a). 相似文献
77.
78.
79.
The new nickel selenite chloride, Ni5(SeO3)4Cl2, was obtained by high-temperature solid state reaction of NiCl2, Ni2O3 and SeO2 in a 1:2:4 molar ratio at 700 °C in an evacuated quartz tube. Its structure was established by single-crystal X-ray diffraction. Ni5(SeO3)4Cl2 crystallizes in the triclinic system, space group P-1 (No. 2) with cell parameters of a=8.076(2), b=9.288(2), c=9.376(2) Å, α=101.97(3), β=105.60(3), γ=91.83(3)° and Z=2. All nickel(II) ions in Ni5(SeO3)4Cl2 are octahedrally coordinated by selenite oxygens or/and chloride anions (([Ni(1)O5Cl], [Ni(2)O4Cl2], [Ni(3)O5Cl], [Ni(4)O6] and [Ni(5)O4Cl]). The structure of the title compound features a condensed three-dimensional (3D) network built by Ni(II) ions interconnected by SeO32− anions as well as Cl− anions. Magnetic property measurements show strong antiferromagnetic interaction between nickel(II) ions. 相似文献
80.
I. I. Kandror M. A. Galkina I. O. Bragina B. D. Lavrukhin Yu. N. Belokon' Yu. G. Gololobov 《Russian Chemical Bulletin》1992,41(10):1928-1930
Ethyl -cyanocarylate undergoes the Michael reaction with strong CH-acids (pK
a < 13) in the presence of strong basic amines such as butylamine, piperidine, and triethylamine. Only polymerization of ethyl -cyanoacrylate occurs under the same conditions with weaker CH-acids in the presence of less basic amines such as aniline, N-methylaniline, and pyridine.A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2449–2452, October, 1992. 相似文献