Monoamides of 5-substituted 4-methyl-3-carboxy-3(or 4)-alkenoic acids have been synthesized, starting with substituted itaconic anhydrides. The anhydride ring was opened by amines to afford N-aryl(or alkyl)-4-alkyl(or aryl)-3carboxy- 3(or 4}-alkenamides. The structure of the amide was elucidated by the comparison with the reference compound prepared from the corresponding Stobbe half-esters.