1 Division of Bioorganic Chemistry, School of Pharmacy, Saarland University, D-66123 Saarbruecken, Germany.
2 CNRS, Centrale Lille, University Lille, UMR 8181-UCCS-Unité de Catalyse et Chimie du Solide, University Artois, F-59000 Lille, France.
3 Departments of Biochemistry and Nutritional Sciences, School of Life Course and Population Sciences, Faculty of Life, Sciences and Medicine, King's College London, Franklin-Wilkins Bldg, 150 Stamford St., London SE1 9NH, UK.