The main purpose of the invention is to provide a novel pyridine derivative or a pharmaceutically acceptable salt thereof. Examples of the invention include a pyridine derivative represented by general formula [1], and a pharmaceutically acceptable salt thereof. This compound or a pharmaceutically acceptable salt thereof exhibits mGluR5 inhibitory activity, and can therefore be used as an agent for the prevention or treatment of, e.g., pain (for example, acute pain, chronic pain, inflammatory pain, neuropathic pain, hyperalgesia, thermal hyperalgesia, allodynia, pain due to noxious thermal stimulation, pain due to noxious mechanical stimulation, pain in the lower urinary tract or reproductive organs, or migraine), pruritus, lower urinary tract symptoms or lower urinary tract disorders, gastroesophageal reflux disease (GERD), gastroesophageal reflux associated with transient lower esophageal sphincter relaxation (TLESR), and diseases of the central nervous system.
