1. Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia, 3-13 50019 Sesto Fiorentino Italy
2. Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq; 71605-170 Brasilia, DF Brazil
3. Department of Chemical Science; University of Padua; Via Marzolo 1 35131 Padova Italy