... membered ring due to the possibility to explore new regions of the chemical space and ... C4 substituents (Schemes 1 and 2). This aspect could be relevant for medicinal chemistry studies but ... 2), further lithiation/substitution would provide all the four stereoisomers C–F. By contrast ...
[Ishibashi, Hiroyuki; Nakatani, Hiroshi; Maruyama, Kazumi; Minami, Kenjiro; Ikeda, Masazumi Journal of the Chemical Society, Chemical Communications, 1987 , # 19 p. 1443 - 1445]