1. REQUIMTE and CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal, CBQ and Department of Chemistry, Central University of Las Villas, Santa Clara, 54830, Villa Clara, Cuba, and Department of Organic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, 15706 Santiago de Compostela, Spain