&NA;MKC 242 is a serotonin 5-HT1Aagonist undergoing phase II trials with Mitsubishi Chemical in Japan as a treatment for anxiety and depression. It is also being investigated in phase II trials in France as a therapy for depression. MKC 242 has potential in the treatment of irritable bowel syndrome, and is currently being investigated preclinically for this indication in Japan.MKC 242 is a potent and selective 5-HT1Areceptor agonist with anxiolytic and antidepressant-like effects in rats. The compound also appears to have an antiobsessional effect. Preclinical results suggest thatMKC 242 has similar pharmacological properties to the azapirones, but may possess a longer-lasting effect.