1. Department of Analytical Sciences and Department of Chemical Development, Boehringer-Ingelheim Pharmaceuticals Inc., 900 Ridgebury Road, Ridgefield, Connecticut 06877, U.S.A., Boehringer-Ingelheim Canada Limited, 2100 Cunard Street, Laval, Quebec H7S 2G5 Canada, and Boehringer-Ingelheim Chemicals Inc., 2820 North Normandy Drive, Petersburg, Virginia 23805, U.S.A.