The competitive N1-, N2-, O- and C-methylation of 3-trifluoromethyl-1H-pyrazol-5-ol for synthesis of analgesic compounds
作者:Ya.V. Burgart、N.A. Agafonova、E.V. Shchegolkov、S.S. Borisevich、S.L. Khursan、V.V. Maslova、G.A. Triandafilova、S.Yu. Solodnikov、O.P. Krasnykh、V.I. Saloutin
DOI:10.1016/j.jfluchem.2018.11.009
日期:2019.2
We have found selective conditions for methylation of 3-trifluoromethyl-1H-pyrazol-5-ol that allowed us to obtain mono-Me-substituted N1- and O-isomers as well N1,N2-, N1,O- and N2,O-disubstituted isomers. A tautomeric structure of the parent pyrazole and its Me-substituted derivatives was investigated using quantum-chemical calculations, X-ray diffraction analysis, IR and NMR spectroscopy. Besides
我们发现了3-三氟甲基-1 H-吡唑-5-醇甲基化的选择性条件,这使我们能够获得单-Me-取代的N 1-和O-异构体以及N 1,N 2-,N 1,O -和N 2,O-二取代的异构体。使用量子化学计算,X射线衍射分析,IR和NMR光谱研究了母体吡唑及其Me取代衍生物的互变异构结构。此外,利用量子化学计算来解释甲基化方向。在体内实验中评估了某些合成化合物的镇痛活性和急性毒性。