1. Department of Chemistry, Federal University of Lavras, P.O. Box 3037, 37200-000,
Lavras, MG, Brazil
2. EaStCHEM School
of Chemistry, University of St Andrews,
North Haugh, St Andrews,
Fife KY16 9ST, U.K.
3. Chemistry
Institute, State University of Campinas, P.O. Box 6154, 13083-971,
Campinas, SP, Brazil