[EN] A PROCESS FOR PREPARATION OF 3,6-DICHLOROCYANO PYRAZINE, 3,6-DIOXOPIPERAZINE DERIVATIVES AND PRODUCTION OF FAVIPIRAVIR THEREOF<br/>[FR] PROCÉDÉ DE PRÉPARATION DE DÉRIVÉS DE 3,6-DICHLOROCYANO PYRAZINE, 3,6-DIOXOPIPÉRAZINE ET PRODUCTION DE FAVIPIRAVIR ASSOCIÉE
申请人:COUNCIL OF SCIENT AND INDUSTRIAL RESEARCH AN INDIAN REGISTERED BODY INCORPORATED UNDER THE REGN OF S
公开号:WO2021250705A1
公开(公告)日:2021-12-16
The present disclosure provides a process for preparation of 3,6-dichlorocyano pyrazine, 3,6-dioxopiperizine derivatives and production of favipiravir via ammonia or amine-mediated cyclization and chlorination using POCl3 in the presence of pyridine or PCl5.[Formula] wherein in 3,6-dioxopiperazine derivatives (III), X is CN, CONH2 or COOR2', R1, R2 and R2' are individually selected from H, C1-C12 alkyl, COOR3 and SO2R3 wherein R3 is substituted or unsubstituted linear or branched lower alkyl.
本公开提供了一种制备3,6-二氯氰基吡嗪、3,6-二氧代哌嗪衍生物以及通过氨或胺介导的环化和氯化,利用POCl3在吡啶或PCl5存在下制备法匹拉韦的方法。其中在3,6-二氧代哌嗪衍生物(III)中,X为CN、CONH2或COOR2',R1、R2和R2'分别选自H、C1-C12烷基、COOR3和SO2R3,其中R3是取代或未取代的线性或支链较低烷基。