已经合成了新型的2-(2-羟苯基)取代的咪唑。已经研究了1-羟基咪唑衍生物的质子互变异构。X射线衍射分析和IR光谱表明,在固态下,标题化合物以N-羟基互变异构体的形式存在。讨论了新咪唑衍生物的1 H和13 C NMR光谱。已经表明,在氯仿溶液中,以N-羟基互变异构形式存在5-羰基取代的2-(2-羟基苯基)-1-羟基咪唑。向DMSO的过渡导致正在研究中的N-氧化物互变异构体1-羟基咪唑的存在。
A group of novel 2-aryl imidazole derivatives were synthesized and characterized by NMR spectra, X-ray, mass and CHN analysis. An excited state intramolecular proton transfer (ESIPT) process in hydroxy imidazoles (dmip and dmtip) have been studied using emission spectroscopy and it was detected that the two distinct ground state rotamers of I and II are responsible for the normal and the tautomer emission respectively. In hydrocarbon solvent, the tautomer emission predominates over the normal emission for both dmip and dmtip. This reveal that rotamer II is responsible for the tautomer emission and it is stabler than rotamer I which causes the normal emission. In alcoholic solvent like ethanol, a dramatic enhancement of normal emission is observed which was due to increased solvation, the more polar rotamer I become stabler than rotamer II. In dioxane—water mixtures it is observed that the addition of water inhibits the ESIPT process due to the formation of the intermolecular hydrogen bonding involving water. DFT calculations on energy, dipole moment, charge distribution of the rotamers in the ground and excited states of the imidazole derivatives were performed and discussed. PES calculation indicates that the energy barrier for the interconversion of two rotamers is too high in the excited state than the ground state.
合成了一组新型2-芳基咪唑衍生物,并通过NMR谱、X射线、质量和CHN分析进行了表征。使用发射光谱研究了羟基咪唑(dmip 和 dmtip)中的激发态分子内质子转移(ESIPT)过程,并检测到 I 和 II 两种不同的基态旋转异构体分别负责正常和互变异构体发射。在烃溶剂中,对于 dmip 和 dmtip,互变异构体发射比正常发射占主导地位。这表明旋转异构体 II 负责互变异构体发射,并且它比导致正常发射的旋转异构体 I 更稳定。在乙醇等醇溶剂中,观察到正常发射的显着增强,这是由于溶剂化增加,极性更强的旋转异构体 I 变得比旋转异构体 II 更稳定。在二恶烷-水混合物中,观察到添加水会抑制 ESIPT 过程,因为涉及水的分子间氢键的形成。对咪唑衍生物的能量、偶极矩、基态和激发态旋转异构体的电荷分布进行了DFT计算并进行了讨论。 PES计算表明,激发态下两个旋转异构体相互转化的能垒比基态高。
Beta3 adrenergic agonists
申请人:——
公开号:US20030191156A1
公开(公告)日:2003-10-09
The present invention relates to a &bgr;
3
adrenergic receptor agonist of formula (I) or a pharmaceutical salt thereof, which is capable of increasing lipolysis and energy expenditure in cells and, therefore, is useful for treating Type II diabetes and/or obesity. The compound can also be used to lower triglyceride levels and cholesterol levels or raise high density lipoprotein levels or to decrease gut motility. In addition, the compound can be used to reduced neurogenic inflammation or as an antidepressant agent. Compositions and methods for the use of the compounds in the treatment of diabetes and obesity and for lowering triglyceride levels and cholesterol levels or raising high density lipoprotein levels or for decreasing gut motility are also disclosed.
The present invention relates to metal complexes and to electronic devices, in particular organic electroluminescent devices, comprising these metal complexes.
本发明涉及金属配合物及包括这些金属配合物的电子设备,特别是有机电致发光器件。
Wadsworth, Journal of the Chemical Society, 1890, vol. 57, p. 11