Crystal structure and physical characterization of N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine, the hydrolysis product of neotame

The hydrolysis product of neotame, N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine (DMBAP), was crystallized from water as an anhydrate with a melting point at 197○C with decomposition. Its crystal structure was determined by single crystal X-ray diffractometry. The crystal is orthorhombic with space group P212_121 with Z=4 and one molecule per asymmetric unit. The cell constants are a=5.520 (2) A, $b=10.608$ (5) A and c= 31.92 (2) A. The 13C solid-state nuclear magnetic resonance spectrum of DMBAP is compared with those of neotame monohydrate and neotame methanol solvate.