Synthesis and SAR of 2,3,3a,4-tetrahydro-1H-pyrrolo[3,4-c]isoquinolin-5(9bH)-ones as 5-HT2C receptor agonists

A series of 2,3,3a,4-tetrahydro-1H-pyrrolo[3,4-c]isoquinolin-5(9bH)-ones is described, several examples of which exhibit potent 5-HT2C agonism with excellent selectivity over the closely related 5-HT2A and 5-HT2B receptors. Compounds such as 38 and 44 were shown to be effective in reducing food intake in an acute rat feeding model.