Method of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylic acid or a derivative thereof
申请人:XINFA PHARMACEUTICAL CO., LTD
公开号:US11142499B1
公开(公告)日:2021-10-12
The present application relates to methods of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylic acid or its derivatives in an environment-friendly way. The method uses L-glutamic acid as a starting material, which is first subjected to esterification reaction in the presence of an acidic reagent, and then reacted successively with 2-haloacetate and N-protecting agent, or with N-protecting agent and 2-haloacetate under a basic condition to obtain compound IV; then, the obtained compound IV is subjected to intramolecular condensation into a ring under the action of a strong base to obtain N-protecting group piperidine-5-one-2S-carboxylate (V).
本申请涉及以环保方式制备5R-[(苄氧基)氨基]哌啶-2S-羧酸或其衍生物的方法。该方法以L-谷氨酸为起始原料,首先在酸性试剂存在下进行酯化反应,然后与2-卤代醋酸酯和N-保护试剂连续反应,或在碱性条件下与N-保护试剂和2-卤代醋酸酯反应以获得化合物IV;然后,所得的化合物IV在强碱作用下进行分子内缩合形成环,得到N-保护基哌啶-5-酮-2S-羧酸酯(V)。