1. Department of Bioengineering , University of California , Riverside, CA 92521 , USA
2. Institute of Organic Chemistry, Polish Academy of Sciences , Kasprzaka 44-52 , 01-224 Warsaw , Poland
3. Department of Chemistry , University of California , Riverside, CA 92521 , USA
4. Department of Biochemistry , University of California , Riverside, CA 92521 , USA
5. GlaxoSmithKline , 200 Cambridgepark Dr. , Cambridge, MA 02140 , USA
6. Materials Science and Engineering Program, University of California , Riverside, CA 92521 , USA