Metalloporphyrin hosts in structural studies by CD/FDCD

An understanding of chirality is a critical issue because of the importance of stereochemistry in biochemistry, biology and biorganic chemistry. The sterochemical assignment of chiral compounds is an important and challenging task since many of the substrates that exhibit important biological activities are only available in minuscule amounts, the development of microscale or even nanoscale spectroscopic methods for the determination of absolute configuration is crucial. One of my goals is to develop a strategy for absolute stereochemical determination of mono-substituted secondary amines, primary alcohols and carboxylic acids. I propose to derivative these compounds with an alchiral diamine reagent which would function as a carrier bringing the chiral guest to a host molecule. This host/guest complexation will yield enantiomeric exciton coupled CD curves, the signs of which reflect the absolute stereochemistry of the guest molecules. Preliminary results show the feasibility of the method. Moreover, I plan to extend this guest chiral recognition technique down to a sub-microscale level where conventional CD signals are no longer detectable through FDCD studies. FDCD measurements are valuable because they will provide a nanoscale tool with a 50 to 100-fold sensitivity enhancement over traditional CD under optimal conditions.