A potent and selective 5-HT4 partial agonist, with a pKi of 8.8 at 5-HT4 sites in guinea pig striatum, but < 6.0 at several other receptors including 5-HT1A, 1D, 2A, 2C, D1, D2 and M1-3. It is active in vivo and has an intrinsic activity compared to 5-HT of 0.6.