organic compounds
The title compound, C27H39N3O9, is a key intermediate in the synthesis of novel β-turn mimetics based on electrophilic amination of enantiomerically pure (S)-pyroglutamic acid. The molecule adopts an extended conformation which is not stabilized by either intra- or intermolecular hydrogen bonding. The pyrrolidine five-membered ring adopts an envelope conformation, with the unsubstituted C atom situated at the flap and the other four atoms almost coplanar.