1. Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Strasse 11 44227 Dortmund Germany
2. Present address: Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai- 400076 Maharashtra India
3. Present address: Syngene International Limited Bengaluru Karnataka 560099 India
4. Faculty of Chemistry and Chemical Biology Technische Universität Dortmund Otto-Hahn Strasse 6 44227 Dortmund Germany