1. Organic
and Biomolecular Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India
2. Nuclear Magnetic Resonance & Structural Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India
3. Institute
of Biochemistry, Faculty of Biosciences, University of Leipzig, Brüderstrasse 34, D-04103 Leipzig, Germany