... WITH A SULFUR YLIDE: THE FORMATION OF A NEW HETEROCYCLIC SYSTEM1) Masafumi YASUNAMI,* Atsushi TAKAGI, and Kahei TAKASE Department of Chemistry, Faculty of Science, Tohoku University Aramaki-aza-Aoba, Sendai 980 ... 3) M. Yasunami, T. Amemiya, and K. Takase, Tetrahedron Lett., in press. 4) P. W. Yang, M. Yasunami, and K. Takase, ibid., 1971, 4275. 5) M. Saito, T. Morita, and K. Takase, Chem. Lett., 1974, 955. ...