To provide a compound that can be used as an MC4 receptor agonist. The inventors studied MC4 receptor agonists, confirmed that a piperazine derivative has an action, and perfected the present invention. Specifically, this piperazine derivative has an MC4 receptor agonist action and can be used as an agent for the prevention and/or treatment of bladder and urinary tract diseases, especially underactive bladder, hypotonic bladder, noncontracting bladder, detrusor muscle hypoactivity, neurogenic bladder, urethral relaxation failure, detrusor-external sphincter incoordination, and dysuria in benign prostatic hyperplasia.
