Babak Borhan
Research
Synthetic and Bioorganic Chemistry
(Research Description PDF)
The research interests of our lab can be subdivided into the three main areas of Bioorganic Chemistry, Synthetic Chemistry, and Organic Spectroscopy.
Our Bioorganic Chemistry efforts are geared towards elucidation of the interaction of bioactive compounds
with receptors and proteins. We rely heavily on de novo protein design and mimicry
of natural systems to better understand how certain biological processes occur. As
an example, we have initiated research into designing protein mimics of rhodopsin,
the protein responsible for vision, which can bind retinal as a protonated Schiff
base [PSB] (same binding mode as in rhodopsin). These protein mimics are used to investigate
the wavelength regulation mechanism that enables color vision. Currently we are exploring
the potential to use our engineered proteins as colorimetric and fluorescent proteins
for cellular tagging and intracellular pH sensors.
Our Synthetic Chemistry program is generally focused on the development of new reactions that utilize simple organic molecules and through designed manipulations lead to more complex systems. In most cases, our methodologies lead to the production of heterocycles with regio- and stereocontrol. These transformations are then highlighted in total syntheses of natural products that exhibit interesting biological activities. Recently we have reported the catalytic asymmetric chlorolactonization of alkenoic acids and unsaturated amides to furnish chiral heterocycles. These reactions are catalyzed by (DHQD)2PHAL in combination with various N-chlorinated hydantoins as the terminal chlorenium sources. Halofunctionalization of different compounds, understanding the mechanism of these transformations and the details of enantioselections are currently under investigation.
In the area of Organic Spectroscopy, we are interested in developing host/guest systems that can be used in the absolute
stereochemical determination of chiral compounds. 
We accomplish this through the design and synthesis of chromophoric receptors, which
upon binding with the chiral compound function as reporters of chirality. We rely
heavily on Circular Dichroism (CD) as the tool for observing the host/guest interactions
between the chiral compounds and the receptors. In particular, we will take advantage
of the excitonic coupling between independently conjugated chromophores that make
up the receptors to establish non-empirical guidelines for the absolute stereochemical
determination of asymmetric centers.