1. Preformulation Department, Pharmaceutical Sciences, Aventis Pharma, Dagenham Research Centre (DRC), Rainham Road South, Dagenham, Essex RM10 7XS, UK, and World-Wide Physical Chemistry Department, Discovery Chemistry, Aventis Pharma, Dagenham Research Centre (DRC), Rainham Road South, Dagenham, Essex RM10 7XS, UK