1. Medical Research Laboratories, Wyeth Lederle Japan, Ltd., 1-6-34 Kashiwa-cho, Shiki-shi, Saitama 353-8511, Japan, Rigaku Corporation, 3-9-12 Matsubara-cho, Akishima-shi, Tokyo 196-8666, Japan, and Chemical & Screening Sciences, Wyeth Research, 401 North Middletown Road, Pearl River, New York 10965