A convenient synthesis of a series of pyrido [3, 2-e][1, 4]-diazepine-2, 5-diones 8 and pyrido [2, 3-e][1, 4] diazepine-2, 5-diones 9, is reported using the condensation of α-amino acid methyl ester derivatives with 1H-pyrido [3, 2-d][1, 3] oxazine-2, 4-dione and 1H-pyrido [2, 3- d][1, 3] oxazine-2, 4-dione. Compounds 8 and 9 were also synthesized by peptide coupling of α-amino acid methyl ester derivatives with β-amino acids (2 or 3) followed by the ...