(2R,3R)-3-O-Benzoyl-N-benzyl­tartramide

The title compound, C(18)H(17)NO(6) [systematic name: (2R,3R)-4-benzyl­amino-2-benzo­yloxy-3-hy­droxy-4-oxobutanoic acid], is the first structurally characterized unsymmetrical monoamide–monoacyl tartaric acid derivative. The mol­ecule shows a staggered conformation around the tartramide Csp(3)—Csp(3) bond with trans-oriented carboxyl and amide groups. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O hydrogen bond. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds between the carboxyl and amide carbonyl groups, forming translational chains along [001]. Further O—H⋯O and N—H⋯O hydrogen bonds as well as weaker C—H⋯O and C—H⋯π inter­molecular inter­actions extend the supra­molecular assembly into a double-layer structure parallel to (100). There are no directional inter­actions between the double layers.