1,2,4-triazine-6-carboxamide derivatives

The following general formula (I) having a Syk inhibitory activity (wherein R1 represents a hydrogen atom or a C1-C6 alkyl group optionally substituted by Ra; A represents a hydrogen atom or Ra substituted) C1-C8 alkyl group, Ra-substituted C2-C6 alkenyl group, Ra-substituted C2-C6 alkynyl group, Rb-substituted C3-C10 cycloalkyl group , Rb may be substituted C6-C14 aromatic hydrocarbon group, Rb may be substituted 4-10 membered unsaturated heterocyclic group, or Rb may be substituted 4-10 membered May represent a saturated heterocyclic group, or together with R1 and the nitrogen atom to which they are attached may form a 4-10 membered unsaturated heterocyclic ring or a 4-10 membered saturated heterocyclic ring; R2 represents hydrogen C1-C6 in which atom or Ra may be substituted Indicates alkyl groups; B is or a salt thereof) showing the Rc is substituted with may be unsaturated heterocyclic group..