1. Department
of Chemistry, University of Southampton, Southampton, Hampshire SO17 1BJ, U.K.
2. Centro de Investigación
Lilly S.A., Avda. de la Industria 30, 28108 Alcobendas-Madrid, Spain
3. Early Chemical Development,
AstraZeneca, Charter Way, Macclesfield, SK10 2NA, U.K.