Synthesis of 5-substituted indole derivatives, part II. Synthesis of sumatriptan through the Japp-Klingemann reaction
Synthesis of selective 5-HT(1B/1D) receptor agonist, sumatriptan (1) was accomplished through decarboxylation of 2-carboxy-3-[2-(dimethylamino)ethyl]- N-methyl-1H-indole-5-methanesulfonamide (2) in quinoline with copper powder. The preparation of the acid (2) was effected through the Japp-Klingemann method thus avoiding the need for the formation of hydrazine from diazonium salt. Attempted decarboxylation in N,N-dimethylacetamide resulted in the formation of the β-carboline (16).