Synthesis of 2,6-dimethylbenzamide N-(5-methyl-3-isoxazolyl) (D2916) labelled with 14C

Carbonation of 2,6-dimethyl phenyl lithium with 14CO2 afforded 2,6-dimethylbenzoic acid, α-14C 2 which was transformed into 2,6-dimethylbenzoic acid halide,α-14C 3. Subsequent condensation of the latter compound with 3-amino 5-methyl isoxazole afforded 2,6-dimethylbenzamide N-(5-methyl-3-isoxazolyl) (D2916) 4 (radiochemical 95% purity) in an overall yield of about 35% based on [14C] barium carbonate. © 1998 John Wiley & Sons, Ltd.