Catalytic, Enantioselective Synthesis of Taranabant, a Novel, Acyclic Cannabinoid-1 Receptor Inverse Agonist for the Treatment of Obesity

Chiral amide 1 ( MK- 0364, taranabant) is a potent, selective, and orally bioavailable cannabinoid-1 receptor ( CB-1R) inverse agonist indicated for the treatment of obesity. An asymmetric synthesis featuring a dynamic kinetic resolution via hydrogenation for the preparation of the bromo alcohol 5 is disclosed. Conversion of the alcohol intermediate to the chiral amide 1 is accomplished in good overall yield.