[Problem] To provide a compound useful as an MCreceptor agonist. [Solution] The present inventors have made studies on MCreceptor agonists. As a result, it is confirmed that a piperazine derivative has an MCreceptor agonist activity, which leads to the accomplishment of the present invention. The piperazine derivative according to the present invention has an MCreceptor agonist activity, and therefore can be used as a prophylactic or therapeutic agent for disturbance of urination in bladder and urinary tract diseases, particularly underactive bladder, hypotonic bladder, acontractile bladder, detrusor underactivity, neurogenic bladder, urethral relaxation failure, detrusor-sphincter dyssynergia and prostatic hyperplasia.
