1. Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
2. GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, U.K.
3. Medicinal Chemistry, Oncology, IMED Biotech Unit, AstraZeneca, 319 Milton Road, Cambridge CB4 0WG, U.K.