The talks are held in the Metcalf Science and Engineering Center, 590 Commonwealth Avenue, Boston, MA. Call 617/353-2500 for further information.
- Talks are held on Wednesdays at 5pm in SCI 294.
- Attendance is limited to students only, unless otherwise noted below.
Spring 2005 Schedule
February 9 |
Tyler Heibeck "Development of a protein 3-nitrotyrosine identification method using solid phase capture" |
February 23 |
John Miecznikowski "Iridium N-Heterocyclic Carbene Complexes in Transfer Hydrogenation Catalysis" |
March 2 |
Patrick Cappillino |
March 9 |
Suzanne Hertzler |
March 16 |
Abby Oelker |
March 23 |
Gulbenk Anarat |
May 4 |
Lauren Wolf |
Tyler Heibeck
3-Nitrotyrosine is produced by the reaction of various redox
reactive nitrogen species, notably peroxynitrite, which is produced under
normal physiological conditions and in increased amounts under conditions
of
oxidant stress. To that end, 3-nitrotyrosine is a potential marker for
oxidative stress induced modifications in proteins. Current detection
methods do not allow for location of the point of modification or are
too
insensitive. Using chemical modification, solid phase capture, and mass
spectrometric analysis 3-nitrotyrosine can be concentrated and identified
within in vitro nitrated protein. Current work is focused on increasing
sensitivity and applicability to complex protein mixtures.
John Miecznikowski
I will describe the synthesis and transfer-hydrogenation activity of
chelating bis-N-heterocyclic carbene complexes of iridium and rhodium.
The chelating bis-N-heterocyclic carbene ligands are robust ligands and,
once bound to the metal, exhibit remarkable thermal, air, and moisture
stability, which are very useful features for homogenous catalysis. These
precatalysts were screened for transfer hydrogenation activity of ketones,
aldehydes, enolizable aldehydes, alpha,beta-unsaturated compounds, and
imines with either potassium hydroxide or alkali carbonates as base.
Chelating bis-imidazole and bis-triazole complexes are prepared and their
activities compared. Variation of the wingtip R-groups is also explored.
A mechanism for transfer hydrogenation of these precatalysts is proposed;
catalyst reuse and selectivity is explored.