Institution: | Shionogi Research Laboratory, Shionogi & Co., Ltd., Fukushima-ku, Osaka, 553 Japan;Service de Chimie Physique, B.P. No. 2, C.E.N. Saclay, 91-Gif-sur-Yvette, France;Institut de Chimie des Substances Naturelles, C.N.R.S., 91-Gif-sur-Yvette, France |