The synthesis of N-acyl derivatives of γ-keto-α-amino acids (3, 4, 5) by the amidoalkylation of 1, 3-dicarbonyl compounds with glyoxylic acid-amide adducts (1, 2) is described. The γ-keto- α-amino acid derivatives (4, 5) were further converted to the corresponding butenolides (6, 7) and to pyrazolylglycine (12).