The present invention provides a novel process for preparing (3R,4R)-1-benzyl-N,4-dimethylpiperidin-3-amine or a salt thereof, which is an intermediate useful for the preparation of tofacitinib. The present invention also provides a novel intermediate used in the process, i.e., isopropanol solvate of methyl ((3R,4R)-1-benzyl-4-methylpiperidin-3-yl)carbamate dibenzoyl-L-tartrate. The present invention also provides a novel intermediate, having excellent stability, useful for the preparation of tofacitinib, i.e., (3R,4R)-1-benzyl-N,4-dimethylpiperidin-3-amine acetate. In addition, the present invention provides a process for preparing tofacitinib or a pharmaceutically acceptable salt thereof using the process.
本发明提供了一种新型制备(3R,4R)-1-苄基-N,4-二甲基
哌啶-3-胺或其盐的方法,该中间体可用于制备
托法替尼。本发明还提供了一种用于该方法的新型中间体,即
甲醇异丙醇溶剂合成的甲基((3R,4R)-
1-苄基-4-甲基哌啶-3-基)
氨基甲酸酯二苯甲酰-
L-酒石酸盐。本发明还提供了一种具有良好稳定性的用于制备
托法替尼的新型中间体,即(3R,4R)-1-苄基-N,4-二甲基
哌啶-3-胺
醋酸盐。此外,本发明还提供了一种使用该方法制备
托法替尼或其药学上可接受的盐的方法。