1. Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, I-53100 Siena, Italy
2. Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, United States
3. Aix-Marseille Université, CNRS, Institut Chimie Radicalaire, 13013 Marseille, France
4. Department of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States