1) Coumarin drug 
Ensaculin (KA-672) is a drug from the coumarin family, which has been researched as a potential treatment for dementia. It acts on a number of receptor systems, being both a weak NMDA antagonist and a 5HT1A agonist. Animal studies have shown promising nootropic effects, although efficacy in humans has yet to be proven. It was well tolerated in hum...