O-Benzyl-N-tert-butoxycarbonyl-N-methyl-L-tyrosine

The crystal structure of the title compound, alternatively called 3-[4-(benzyloxy)phenyl]-2-(N-tert-butoxycarbonyl-N-methylamino)propionic acid, C(22)H(27)NO(5), has been studied in order to examine the role of N-methylation as a determinant of peptide conformation. The conformation of the tert-butoxycarbonyl group is trans-trans. The side chain has a folded conformation and the two phenyl rings are effectively perpendicular to one another. The carboxylate hydroxyl group and the urethane carbonyl group form a strong intermolecular O[bond]H...O hydrogen bond.