The benzene and ethanol solvates of neotame crystallized from solutions of neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P21, Z = 2, with one neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and β = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P2 12121 with Z = 8 (Z′ = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the neotame molecules.
Bibliographical noteFunding Information:
We thank The NutraSweet Company for partial financial support and the United States Pharmacopeial Convention for the award of a USP Fellowship in Drug Standards Research to Zedong Dong. We also thank the Supercomputer Institute of the University of Minnesota for supporting our use of the Medicinal Chemistry/Supercomputing Institute Visualization-Workshop Laboratory. In addition, we thank Novartis Corporation for a Graduate Research Fellowship and Pharmacia Corporation for an Enz award, both to Zedong Dong. Use of the ChemMatCARS Sector 15 at the Advanced Photon Source is supported by the National Science Foundation/Department of Energy under grant numbers CHE9522232 and CHE0087817 and by the Illinois Board of Education. Moreover, the Advanced Photon Source is supported by the US Department of Energy, Basic Energy Sciences, Office of Science, under contract no. W-31-109-Eng-38. A special word of thanks goes to David Cookson, Jeff Gebhardt, and Timothy Graber who assisted in these measurements during the commissioning run for the microcrystallography beamline.
- Benzene solvate
- Ethanol solvate
- Hydrogen bonding
- Hydrophobic region
- Synchrotron diffraction