Synthesis of bistable azodianiline analogs for applications in light-gated ion channels

WCC 15

Hanna M. Wisniewska1, Matthew R. Banghart, matt_b@berkeley.edu1, Jessica H Harvey, jharvey@berkeley.edu1, Katharine Borges2, Ehud Y Isacoff3, Richard H. Kramer3, and Dirk Trauner1. (1) Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, (2) Department of Molecular and Cellular Biology, University of California, Berkeley, Berkeley, CA 94620, (3) Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-1460
Recently, several light-gated ion channels have been engineered using azobenzene-based tethered-ligands to afford optical control of electrical activity in neurons. Unfortunately, the propensity of cis azobenzene to undergo spontaneous thermal relaxation to the trans form in the dark limits the use of these technologies. A series of sterically hindered azodianilines was therefore synthesized, in which methyl groups were systematically added ortho to the azo bond. The analogues were prepared from commercially available precursors via either oxidative coupling or diazo coupling to form the key azo bond. The tetramethyl derivative (tmMAQ) exhibited a 400-fold increase in half life over the parent unmethylated compound, MAQ. This result demonstrates that adding steric bulk ortho to the azo bond in azobenzenes is a viable and effective way of improving cis isomer half-life. A detailed evaluation of the entire series is currently underway.
 

Many Faces of Chemistry: Merck Index Women in Chemistry
1:00 PM-3:00 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Poster

Women Chemists Committee

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007