Crystal structure of dimethyl N,N′-[(ethyne-1,2-di­yl)bis­(1,4-phenyl­enecarbon­yl)]bis­(l-alaninate)

The di­phenyl­ethyne unit of the title mol­ecule, C(24)H(24)N(2)O(6), deviates slightly from planarity. The l-alanine moieties adopt distorted helical conformations of opposite winding direction. Infinite ribbons of N—H⋯O=C-connected mol­ecules represent the basic supra­molecular entities of the crystal structure. These aggregates are linked by C—H⋯O hydrogen bonds involving the oxygen atoms of the methyl carboxyl­ate units. The crystal studied was refined as an inversion twin.