Novel (R)-6,6a,7,8,9,10-hexahydro-5H-pyrazino[1,2-a][1,n]naphthyridines as potent and selective agonists of the 5-HT receptor.

A series of novel (R)-6,6a,7,8,9,10-hexahydro-5H-pyrazino[1,2-a][1,n]naphthyridines were identified as potent and selective agonists of the 5-HT receptor. Optimizations performed on a previously reported series of racemic tetrahydroquinoline-based tricyclic amines, delivered an advanced drug lead, (R)-4-(3,3,3-trifluoropropyl)-6,6a,7,8,9,10-hexahydro-5H-pyrazino[1,2-a][1,8]naphthyridine, which displayed excellent in vitro and in vivo pharmacological profiles.

Tetrahydroquinoline-based tricyclic amines as potent and selective agonists of the 5-HT receptor.

The syntheses, structure-activity relationships (SARs), and biological activities of tetrahydroquinoline-based tricyclic amines as 5-HT receptor agonists are reported. An early lead containing a highly unique 6,6,7-ring system was optimized for both in vitro potency and selectivity at the related 5-HT receptor. Orally bioactive, potent, and selective 6,6,6-tricyclic 5-HT agonists were identified.