NOVEL NICOTINAMIDE DERIVATIVE OR SALT THEREOF

摘要

The object of the present invention is to provide a compound and a pharmaceutical composition having excellent Syk inhibitory activity. According to the present invention, a nicotinamide derivative represented by the following formula (I) or a salt thereof is provided,
wherein
R 1 is a substituent represented by the following formula (II-1), (III-1), or (IV-1)
(wherein R 3 , R 4 , R 5 , n, and X 1 have the same definitions as those described in the specification), and R 2 is a pyridyl, indazolyl, phenyl, pyrazolopyridyl, benzisoxazolyl, pyrimidinyl, or quinolyl group, each of which optionally has at least one substituent.