AS19 is a potent, selective 5-HT7 receptor agonist with an IC50 value of 0.83 nM and a Ki of 0.6 nM. AS19 is selective for 5-HT7 over 5-HT1A, 5-HT1B, 5-HT1D, and 5-HT5A receptors (Kis = 89.7 nM, 490 nM, 6.6 nM and 98.5 nM, respectively). AS19 enhances memory consolidation and reverses Scopolamine- or Dizocilpine-induced amnesia. In Vitro: The proliferation of T-cell from parachlorophenylalanine-treated mice is significantly reduced, addition of AS19 (1 μM) completely restores T-cell proliferation after 48 hours. In Vivo: AS19 (0.5-10 mg/kg; subcutaneous injection; for 24 hours; male Wistar rats) treatment improves memory consolidation in an autoshaping Pavlovian/instrumental learning task.