Conformational switching of aromatic amides

ORGN 142

Aya Tanatani, aya@iam.u-tokyo.ac.jp1, Ryu Yamasaki2, Naoaki Kabasawa1, Yuichi Hashimoto1, Isao Azumaya3, and Hiroyuki Kagechika, kage.omc@tmd.ac.jp4. (1) Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032, Japan, (2) Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan, (3) Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa, 769-2193, Japan, (4) School of Biomedical Science, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan
Regulation of molecular conformations and dynamic behaviors is significant in the construction of structurally well-ordered macromolecules or application to molecular switches and molecular recognition events. During our investigations on the aromatic amides with cis conformational preference, we found several types of aromatic amides altered the conformation induced by the external conditions. First, N-methylacetanilides with an amino substituent on the aromatic ring prefer the cis conformation, while the addition of acid caused the amide conformational switching. Second, N-(dihydroxyphenyl)-N-phenylacetanilide changed its stable conformation by oxidation. Third, N-phenylhydoxamic acids exist in cis conformation in methylene chloride, while the trans conformer is predominant in methanol or acetone. Interestingly, the crystals obtained from methylene chloride or acetone included cis and trans conformers, respectively. These conformational properties could be applied to develop external conditions-sensitive molecular machines.
 

Heterocycles, Aromatics, Materials, Devices, Switches, Combinatorial Chemistry, Metal-Mediated Reactions
8:00 PM-10:00 PM, Sunday, 13 March 2005 Convention Center -- Hall D, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 14 March 2005 Convention Center -- Sails Pavilion, Sci-Mix

Division of Organic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005