N,N'-Dimethyl-N,N'-diphenyl-3-oxa-penta-nediamide.

In the title compound, C(18)H(20)N(2)O(3), the two phenyl rings, adopt opposite orientations in the backbone and are oriented at a dihedral angle of 36.66 (3)°. In the crystal, inter-molecular C-H⋯O inter-actions link the mol-ecules into a three-dimensional network.

(-)-Dimethyl 3,3'-diphenyl-2,2'-[pyridine-2,6-diylbis(carbonyl-imino)]dipropanoate.

The title compound, C(27)H(27)N(3)O(6), a bis-amide derivative, is also a chiral amino acid ester with l-phenyl-alanine methyl ester groups as amine substituents. The pyridine ring is oriented at dihedral angles of 89.69 (3) and 62.95 (3)° with respect to the phenyl rings, while the dihedral angle between the phenyl rings is 60.76 (3)°. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains. One of the carbonyl O atoms and one of the meth-oxy CH(3) groups are disordered over two positions. The O atom was refined with occupancies of 0.69 (13) and 0.31 (13), while C and H atoms were refined with occupancies of 0.69 (8) and 0.31 (8).