1. Department of Chemistry and Centre for Green Chemistry, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, MA 02125, USA
2. Department of Cancer Biology Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
3. Department of Chemistry, Changchun Normal University, Changchun 130032, P. R. China
4. Department of Chemistry, Keene State College, Keene, NH 03435, USA