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
R1 is a substituent represented by the following formula (II-1), (III-1), or (IV-1)
(wherein R3, R4, R5, n, and X1 have the same definitions as those described in the specification), and R2 is a pyridyl, indazolyl, phenyl, pyrazolopyridyl, benzisoxazolyl, pyrimidinyl, or quinolyl group, each of which optionally has at least one substituent.
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.