三梅片成份分析研究

医药品冰片有天然品与合成品之分,天然品有:由龙脑香科(Dipterocarpaceae)植物龙脑香(Dryobalanops aromatica G aertn,f.)制得的结晶,称龙脑香冰片;白菊科(Compositae)植物艾纳香(Blumea balsamifera DC.)所得的结晶,名艾片。艾片因其晶形似梅花片,又有梅片之称,根据梅花片状又分为大梅片,二梅片,三梅片,天然品化学成分为龙脑(Borneol,Ⅰ),合成冰片(又名合成龙脑),除含龙脑外尚含较大量的异龙脑(ISO-borneol,Ⅱ)     

甲醛在Ni(110)面上分解的分子轨道研究

本文应用CNDO方法研究了H_2CO在Ni(110)面上的分解反应。证明了金属镍使H_2CO对称禁阻的热分解反应变成了对称允许反应; 讨论了H_2CO在Ni(110)面上的各种吸附模型; 论证了卧式多中心吸附作为H_2CO分解的中间步骤。     

Equilibrium NH-acidity of 1,4-dihydropyridines and 4,5-dihydroindeno[1,2-b]pyridines

The patterns governing the dependence of NH-acidity on the presence of -, - and -substituents in the 1,4-dihydropyridine ring and on their nature have been established by comparison of the pK_a values of monocyclic 1,4-dihydropyridines and 4,5-dihydroindenopyridines. Additional data were obtained on the influence of the the electronic effects of sulfur-containing substitutents on the reaction center in the dihydropyridine molecules.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1228–1231, September, 1989.     

三缺位α-9钨镓杂多酸盐的合成与性质

本文报道了一种新的三缺位杂多阴离子α-[GaW_9O_(34)H_2]~(9-)的钠、钾、四甲基铵盐的合成方法,并通过元素分析、红外、紫外、极谱、热分析等方法对它进行了表征。α-[GaW_9-O_(34)H_2]~(9-)是一具有三个空位的杂多阴离子,它能与过渡金属离子反应生成具有Keggin结构的三取代钨镓杂多阴离子[GaW_9O_(37)M_3(H_2O)_3]~(R-)。     

A copper- and amine-free sonogashira reaction employing aminophosphines as ligands

An efficient Pd-catalyzed Sonogashira coupling reaction was achieved in the absence of a copper salt or amine with an inorganic base and easily prepared, air-stable aminophosphine ligands in commonly used organic solvents; good to excellent yields were obtained. Under optimized reaction conditions, the Sonogashira coupling reaction occurred selectively when an enyne substrate was employed and no Heck reaction product was detected; acetone-masked acetylene and trimethylsilylacetylene can also be efficiently coupled, providing a method to make terminal alkynes.     

Measurement of the half life of126Sn using a radiochemical method

The half-life of¹²⁶Sn has never been measured accurately. The value quoted in the literature is approximately 10⁵y, which was measured in 1958. In the present work we measured accruately the half life of¹²⁶Sn to be (2.5±0.2)×10⁵y using a radiochemical method.     

Design of New Water Receptors Based on Oligomeric Complexes of Copper(II) and Nickel(II)

The interaction of mono- and oligomacromolecular complexes of copper(II) and nickel(II) with water vapor has been studied on a piezoquartz microbalance. It has been established that the effectiveness of adsorption is determined by the nature of the metal ion to a larger extent than the quantity of macrocyclic ligand in the receptor molecule. Oligomacrocyclic complexes of copper(II) are shown to have prospects for use as active coverings of moisture meters working over a wide range of relative humidity.     

Composition of Laprol-373 and Products of Its Reaction with 2,4-Toluylene Diisocyanate

The composition of oligoethers that are components of Laprol-373 and of products of their reaction with 2,4-toluylene diisocyanate were studied by matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF).