2-(咪唑并[1,2-a]吡啶-3-基)乙酸的合成工艺改进

Improved synthesis of 2-( imidazo[1,2-a] pyridin-3-yl) acetic acid

目的改进骨质疏松治疗药米诺膦酸的关键中间体2-(咪唑并[1,2-a]吡啶-3-基)乙酸的合成工艺。方法以反式-4-氧基-2-丁烯酸乙酯和2-氨基吡啶为起始原料,经环合、水解得到2-(咪唑并[1,2-a]吡啶-3-基)乙酸。结果与结论该合成方法首次以纯水替代有机溶剂作为反应溶剂,采用"一锅法"合成目标化合物,降低了该中间体的制备成本,而且环境友好,更适合于工业化生产。

2-（ Imidazo[ 1,2-α ] pyridin-3-yl ）acetic acid is the key intermediate of minnodronic acid, which was used to the treatment of osteoprosis. An improved synthetic method of 2-（ imidazo[ 1,2-α] pyridin-3-yl） acetic acid（I） was designed based on the public patent literature. The intermediate was synthesized from 2- amino pyridine via＂ one-pot＂reaction. Water was used as the reaction solvent instead of organic solvents for the first time and the total yield was up to 90. 9%. So the improved process not only reduced the costs,but also was more environmentally benign and more conducive to industrial production.