Synthesis of methyl(ethyl) pyrazolo[4,3-b]pyridine-6-carboxylates and their conversion to tert-butyl 4,5,6,7-tetrahydropyrazolo-[4,3-b]pyridine-6-carboxylates
作者:Georgiy G. Yakovenko、Lesya N. Saliyeva、Eduard B. Rusanov、Il’ya S. Donchak、Mykhailo V. Vovk
DOI:10.1007/s10593-021-03032-z
日期:2021.11
N-Boc-4-aminopyrazole-5-carbaldehydes react with methyl 3,3-dimethoxypropanoate or β-keto esters in acetic acid under reflux to form methyl(ethyl) pyrazolo[4,3-b]pyridine-6-carboxylates, which were converted to the corresponding tert-butyl carboxylates via intermediate carboxylic acids. Their subsequent hydrogenation on a 10% Pd/C catalyst at 100°C and 25 atm afforded tert-butyl 4,5,6,7-tetrahydropyrazolo[4
N -Boc-4-氨基吡唑-5-甲醛与3,3-二甲氧基丙酸甲酯或β-酮酯在乙酸中回流反应生成吡唑并[4,3 - b ]吡啶-6-羧酸甲酯(通过中间体羧酸转化为相应的羧酸叔丁酯。它们随后在 10% Pd/C 催化剂上在 100°C 和 25 个大气压下氢化,得到4,5,6,7-四氢吡唑并[4,3 - b ]吡啶-6-羧酸叔丁酯。
LE HAO DONG P.; COQUELET C.; BASTIDE J.-M.; LEBECQ J.-C., EUR. J. MED. CHEM.-CHIM. THER., 1981, 16, NO 1, 39-42