[1] Univ Ottawa, Dept Chem, Ottawa, ON K1N 6N5, Canada
[2] Univ Veszprem, Dept Organ Chem, Muller Lab, H-8200 Veszprem, Hungary
[3] Univ Essen Gesamthsch, Inst Inorgan Chem, D-45117 Essen, Germany
[4] Univ Roma La Sapienza, Dept Chem & Technol Biol Act Compounds, I-00185 Rome, Italy
[5] Univ Modena, Dept Chem, I-41100 Modena, Italy