1. Institute for Organic Chemistry and Chemical Biology Center for Biomolecular Magnetic Resonance (BMRZ) Goethe University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt/Main Germany
2. Laboratory of Clinical Neurochemistry Department of Medicine and Surgery University of Perugia Piazzale Lucio Severi 1/8 06132 Perugia Italy
3. Chemistry Department University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
4. Magnetic Resonance Center (CERM/CIRMMP) University of Florence Via Luigi Sacconi 6 50019 Sesto Fiorentino Italy
5. Institute for Physical and Theoretical Chemistry Goethe University Frankfurt Max-von-Laue-Str. 9 60438 Frankfurt/Main Germany
6. Institute for Organic Chemistry University of Duisburg-Essen Universitätsstrasse 7 45117 Essen Germany