Our focus in the Ashby Group is the synthesis of functional shape memory materials for biomedical applications. We have recently reported the topological control of mesenchymal stem cells by responsive poly(ε-caprolactone) surfaces in which we engineered a biocompatible shape memory surface to mechanically alter stem cell topology.
Group members are also developing scaffolds for nitric oxide release in collaboration with the Schoenfisch Group, and are working towards the synthesis of new iodinated polyesters for use in X-ray computed tomography.
Members of the Erie Group focus on using single molecule and biochemical methods to better understand the kinetics and thermodynamics of protein-nucleic acid interactions. Current single molecule techniques used in the lab include Atomic Force Microscopy (AFM) and Total Internal Reflection Microscopy (TIRM) techniques such as Fluorescence Resonance Energy Transfer (FRET). A major focus of our lab is the characterization of both the static and the dynamic protein-nucleic acid interactions that govern the overall repair specificity of mismatched or damaged DNA in prokaryotic and eukaryotic organisms. A few questions we are addressing include the following: How is mismatch repair initiated on some mismatches but not others? What properties of a damaged DNA substrate initiate apoptosis over mismatch repair? What roles do the mismatch repair initiation proteins, MutS and MutL, play in that separation of pathways? What are the structures/conformations of the multi protein-DNA complexes that control DNA repair? We are also characterizing a host of other protein-DNA interactions involved in DNA repair. There are projects within the group that would appeal to most areas of interest. Our group is composed of students from a variety of backgrounds and departments including chemistry, materials science, physics, and biophysics.
Carolina Chemistry's David Nicewicz has received the 2013 New Investigator Award in Organic Chemistry. Sponsored by Boehringer Ingelheim, the world's largest privately held pharmaceutical company, the award of $50,000 will be given to David towards the funding of a post-doctoral fellow in his laboratory.
The Nicewicz Group conducts research in the broadly defined fields of asymmetric catalysis and target-oriented synthesis. Concerning the area of asymmetric catalysis, the group focuses primarily on the development of novel catalytic processes to access highly reactive intermediates under operationally mild conditions. Methods encompassing the general areas of electron transfer and atom abstraction are of particular interest.
Congratulations to Professor Joseph DeSimone and former lab members, Jason Rolland and Ben Maynor, are winners of the 2014 Kathryn C. Hach Award for Entrepreneurial Success from the American Chemical Society!
The winners will be formally presented with the award during a March 2014 National Awards Ceremony at the ACS National Meeting in Dallas. The award recognizes the team's successful efforts to commercialize the PRINT® technology after it was invented in the DeSimone lab in 2004.
Published in Analytical Chemistry, scientists in the Allbritton Group in collaboration with colleagues from Pharmacology, Biostatistics and Endodontics, and Biomedical Engineering, all at UNC, and the National Health and Environmental Effects Research Laboratory, describe a novel method for the measurement of protein tyrosine phosphatase, PTP, activity in single human airway epithelial cells, hAECs, using capillary electrophoresis.
Their technique involved the microinjection of a fluorescent phosphopeptide that is hydrolyzed specifically by PTPs. Initial results were then extended to a more physiologically relevant model system: primary hAECs cultured from bronchial brushings of living human subjects. The results demonstrate the utility and applicability of this technique for the ex vivo quantification of PTP activity in small, heterogeneous, human cells and tissues.
Michael Corbett, PhD, from the Johnson Group, describes in Angewandte Chemie how dynamic kinetic asymmetric transformations (DyKAT) of racemic β-bromo-α-keto esters by direct aldolization of nitromethane and acetone provide access to fully substituted α-glycolic acid derivatives bearing a β-stereocenter.
The aldol adducts are obtained in excellent yield with high relative and absolute stereocontrol under mild reaction conditions. Mechanistic studies determined that the reactions proceed through a facile catalyst-mediated racemization of the β-bromo-α-keto esters under a DyKAT Type I manifold.
Researchers in the Johnson Group, published in JACS, describe an asymmetric total synthesis of the aminocyclopentitol pactamycin. The title compound is delivered in 15 steps from 2,4-pentanedione. Critical to this approach was the exploitation of a complex symmetry-breaking reduction strategy to assemble the C1, C2, and C7 relative stereochemistry within the first four steps of the synthesis.
The article describes multiple iterations of this reduction strategy, and a thorough analysis of stereochemical outcomes is also detailed. In the final case, an asymmetric Mannich reaction was developed to install a protected amine directly at the C2 position. Symmetry-breaking reduction of this material gave way to a remarkable series of stereochemical outcomes leading to the title compound without recourse to nonstrategic downstream manipulations. This synthesis is immediately accommodating to the preparation of structural analogs.
Scientists in the Johnson Group, in collaboration with researchers from GlaxoSmithKline, as published in Organic Letters, show how a high throughput screening enabled the development of a copper-based catalyst system for the asymmetric hydrogenation of prochiral aryl and heteroaryl ketones that operates at H2 pressures as low as 5 bar.
A ligand combination of (R,S)-N-Me-3,5-xylyl-BoPhoz and tris(3,5-xylyl)phosphine provided benzylic alcohols in good yields and enantioselectivities. The electronic and steric characteristics of the ancillary triarylphosphine were important in determining both reactivity and selectivity.
At the Department of Chemistry, we feel strongly that diversity is crucial to our pursuit of academic excellence, and we are deeply committed to creating a diverse and inclusive community. We support UNC's policy, which states that "the University of North Carolina at Chapel Hill is committed to equality of opportunity and pledges that it will not practice or permit discrimination in employment on the basis of race, color, gender, national origin, age, religion, creed, disability, veteran's status, sexual orientation, gender identity or gender expression."