1. Centre for Advanced Studies in Chemistry; North-Eastern Hill University; Shillong 793 022 India
2. Centre for Molecular Modeling; CSIR-Indian Institute of Chemical Technology; Hyderabad 500 007 India
3. Department of Zoology; Cotton College State University; Guwahati 781 001 India
4. Department of Pharmacy, School of Applied Sciences; University of Huddersfield; Huddersfield HD1 3DH UK
5. Department of Chemistry; University of Washington; Seattle WA 98195 U.S.A.