1. 1) T. Nozoe, S. Seto, S. Ebine, and S. Ito, J. Am. Chem. Soc., 73, 1895 (1951). This is designated as Part 1 of this series.
2. 2) T. Nozoe and S. Seto, Proc. Japan Acad., 27, 188 (1951).
3. 3) Microanalyses were carried out by Messrs. Hirai and Kawamoto of the Sankyo Co., Ltd.
4. 4) T. Nozoe, Y. Kitahara, K. Yamane, and A. Yoshikoshi, Proc. Japan Acad., 27, 18 (1951).
5. 5) Reaction with benzaldehyde is very difficult, only once a product of m.p. 127-128° was obtained.