PROCESSES FOR THE PREPARATION OF ROXADUSTAT AND INTERMEDIATES THEREOF

    公开(公告)号:WO2021026307A1

    公开(公告)日:2021-02-11

    申请号:PCT/US2020/045128

    申请日:2020-08-06

    IPC分类号: C07D217/26

    摘要: The present invention provides new procedure and intermediates for the preparation of Roxadustat (1) comprising: (A) reducing a compound of formula 3', 3" or a mixture thereof: (3'), (3") wherein Pg is H or a OH protecting group, Ri is alkyl, aryl, or arylalkyl; R 2 , R 3 , R 4 , and Rs each independently represents alkyl, arylalkyl or alkenyl, or R 2 and R 3 and/or R 4 and Rs, taken together with the nitrogen atom to which they are bonded, each independently form a ring selected from: (I), wherein R 6 is H or C I- 6 alkyl; R 7 is Ci to C6 alkyl and X- is an anion selected from the group consisting of halide, O-SO 4 -R 7 wherein R 7 is Ci to C 6 alkyl, or O-SO 2 -Rs wherein Rs is phenyl, tolyl, methyl or trifluoromethyl; to form a compound of formula (2') wherein Pg is H or an OH protecting group, Ri is alkyl, aryl, or arylalkyl; and removing the Ri group and where present removing the OH protecting group; or (B) reducing a compound of formula 4', a compound of formula 4" or a mixture thereof: (4'), (4") wherein Pg is H or an OH protecting group; Ri is H, alkyl, aryl, or arylalkyl; R 2 , R 3 , R 4 , and R5 each independently represents alkyl, aryl, arylalkyl or alkenyl; or R 2 is Ci- 4 alkyl and R 3 is Ci- 4 alkoxy; or R 2 and R 3 and/or R 4 and R 5 , taken together with the nitrogen atom to which they are bonded, each independently form a group selected from: (I) wherein R 6 is H or C I-6 alkyl; and where Ri is not H, removing the Ri group, and, where present removing the OH protecting group.