The present invention relates to a pyridine derivative of formula (1) wherein R1 is optionally-substituted C1-6 alkyl, optionally-substituted C3-10 cycloalkyl, or optionally-substituted 5- to 10-membered saturated or partially-unsaturated heterocyclyl; R2 is halogen atom, cyano, C1-6 alkyl which may be optionally substituted with 1 to 3 the same or different halogen atoms, C1-6 alkoxy which may be optionally substituted with 1 to 3 the same or different halogen atoms, or amino which may be optionally substituted with 1 to 2 the same or different C1-6 alkyl; and the bind with broken line is single or double bond, or a pharmaceutically acceptable salt thereof, which is useful as a medicament for treating symptoms in anxiety-related disorder.