Pentafluorophenyl (3 R ,4 R ,5 R )‐5‐{[(3 R ,4 R ,5 R )‐5‐azidomethyl‐3,4‐dimethoxy‐2,3,4,5‐tetrahydrofuran‐3‐carbonylamino]methyl}‐3,4‐dimethoxy‐2,3,4,5‐tetrahydrofuran‐3‐carboxylate

The crystal structure of the title compound, C 22 H 25 F 5 N 4 O 9 , an important intermediate in the synthesis of novel biopolymers containing branched carbon chains, establishes the relative stereochemistry at all six chiral centres of the dipeptide. The structure may indicate a predisposition to the organization of secondary structure by novel dipeptide isosteres. An intermolecular hydrogen bond between the NH group and one of the N atoms of the azide group contributes to the stabilization of the packing.