1. Department of Organic Chemistry; Indian Institute of Science, CV Raman Road; Bengaluru 560012 India
2. Medicinal and Process Chemistry Division; CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road; Lucknow 226031 India
3. Centre for Nuclear Magnetic Resonance; SAIF; CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road; Lucknow 226031 India
4. Laboratoire des Glucides (UMR 6912); CNRS-FRE-3517; Universit de Picardie Jules Verne, 33, Rue St Leu, Faculte des Sciences; Amiens 80039 France