Sematilide is an antiarrhythmic agent. It is the same structure as for procainamide, differing only by the placement of a mesyl sulfonamide moiety to the anilino nitrogen.
Sematilide can be synthesized from benzocaine (1).[1] [2] Reaction with mesyl chloride, followed by saponification and removal of the water from the reaction mixture, gives sodium 4-[(methylsulfonyl)amino]benzoate (2). Chlorination with thionyl chloride gives 4-[(methylsulfonyl)amino]benzoyl chloride. Amide formation with N,N-diethylethylenediamine (3) then concludes the synthesis of sematilide (4).
