1. Process Research, Banyu Pharmaceutical Co., Ltd., Japan 9‐1, Kamimutsuna 3‐Chome, Okazaki, Aichi 444‐0858, Japan, Fax: +81‐564‐51‐7086
2. Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA, Fax: +1‐773‐702‐0805