1. Laboratory of Bioinorganic Chemistry, Department of Organic and Inorganic Chemistry, Federal University of Ceara, 60455-760, Fortaleza-CE, Brazil
2. Department of Physiology and Pharmacology, School of Medicine, Federal University of Ceara, Coronel Nunes de Melo St., 1127, 60.430-275, Fortaleza-CE, Brazil
3. Drug Research and Development Center (NPDM), Federal University of Ceara, Coronel Nunes de Melo St., 1000, 60.430-275, Fortaleza-CE, Brazil
4. National Cancer Institute, Cancer and Inflammation Program, Frederick, Maryland 21702, USA