1. Department of Chemistry; University of Agriculture; Faisalabad Pakistan
2. Natural Product and Synthetic Chemistry Lab.; Department of Chemistry; Government College University; Faisalabad Pakistan
3. Key Laboratory of Magnetic Resonance in Biological Systems; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Centre for Magnetic Resonance; Wuhan Institute of Physics and Mathematics; Chinese Academy of Sciences; Wuhan 430071 P. R. China
4. University of Chinese Academy of Sciences; Beijing 100049 P. R. China
5. Department of Biochemistry; University of Agriculture; Faisalabad Pakistan
6. Institute of Medical and Biomedical Education; St George's, University of London; Tooting London SW17 0RE UK