A novel amine derivative expressed by general formula (1) (in the formula: G 1 , G 2 , and G 3 are the same or different and represent CH or a nitrogen atom； R 1 represents a chlorine atom, an optionally-substituted C 3-8 cycloalkyl group, or the like； R 2 represents -COOR 5 (in the formula, R 5 represents a hydrogen atom or a carboxyl protective group), or the like； R 3 represents a hydrogen atom, or the like； and R 4 represents an optionally-substituted condensed bicyclic hydrocarbon group, an optionally-substituted bicyclic heterocyclic group, or the like), or a salt thereof is useful in procedures such as the treatment or prevention of conditions related to excessive keratinocyte proliferation.
