trans-2-Aminocyclohexanols as pH-triggered molecular switches

CHED 331

Barbora Brazdova, b_brazdova@pacific.edu, Sombo Koo, vsamoshin@pacific.edu, Yuen Shan Wong, b_brazdova@pacific.edu, Andreas H. Franz, afranz@pacific.edu, and Vyacheslav V. Samoshin, vsamoshin@pacific.edu. Department of Chemistry, University of the Pacific, 3601 Pacific Ave., Stockton, CA 95211
The cyclohexane-based conformationally controlled molecular switches provide a new and promising approach to allosteric systems with negative cooperativity. Protonation of trans-2-aminocyclohexanols leads to dramatic conformational changes: due to an intramolecular hydrogen bond, a conformer with equatorial position of ammonio- and hydroxy-groups becomes predominant. This ‘impulse' is mechanically transmitted by the structure of the molecule, inducing a conformational change in the second site, thus altering its properties, e.g. decreasing its affinity to an appropriate guest. Thus, these structures can serve as powerful conformational pH-triggers. The variation of NR2 groups allows a broad tuning of the conformational equilibrium. Heterotropic allosteric systems with high negative cooperativity may find many applications, such as a design of switchable ionophores for membrane transport.

 

Undergraduate Research Poster Session: Organic Chemistry
2:30 PM-4:30 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Poster

Division of Chemical Education

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006