2,2'-(Biphenyl-2,2'-diyldi-oxy)diaceto-hydrazide.

In the mol-ecule of the title compound, C(16)H(18)N(4)O(4), the dihedral angle between the mean planes of the two benzene rings is 56.76 (5)°. The crystal structure reveals extensive inter-molecular hydrogen bonds between carbonyl O atoms and primary amines, as well as between primary and secondary amines of hydrazide, forming rings of R(2) (2)(10) and R(2) (2)(6) motifs, respectively. The structure is further stabilized by intra-molecular and non-classical hydrogen bonds of the types N-H⋯O and C-H⋯O, respectively. The structure does not show any π-π inter-actions.

Di-tert-butyl 2,2'-(biphenyl-2,2'-diyl-dioxy)diacetate.

The title compound, C(24)H(30)O(6), does not exhibit π-π inter-actions due to the steric effect of the bulky tert-butyl groups present in the mol-ecule. The presence of these groups at the 2 and 2' positions hinders the free motion of the benzene rings relative to each other, causing them to adopt an anti-periplanar arrangement. The benzene rings are twisted by just under 50.96 (17)° with respect to each other. The carbonyl groups within the mol-ecule are directed in different directions, one towards the biphenyl group and the other away from it. The mol-ecules are linked together by C=O⋯H-C hydrogen bonds.