1. a Medical Research Council, Laboratory of Molecular Biology , Hills Road, Cambridge , CB2 2QH , UK
2. e ArQule Inc , 19 Presidential Way, Woburn , MA , 01801 , USA
3. b Cambridge Crystallographic Data Centre , 12 Union Road, Cambridge , CB2 1EZ , UK
4. c Nycomed Amersham plc, Amersham Laboratories , White Lion Road, Amersham , Buckinghamshire , HP7 9LL , UK
5. d Amersham Pharmacia Biotech , 800 Centennial Ave., Piscataway , NJ , USA