1. 1) K. Yamasaki and I. Ushizawa: Proc. Japan Acad., 28, 546, 550 (1952).
2. 2) Ch. Mystre, H. Frey, R. Neher, A. Wettstein, and A. Miescher: Helv. Chim. Acta, 29, 627 (1946).
3. K. Takeda and J. Kawanami: J. Biochem., 40, 477 (1935);
4. Helv. Chim. Acta., 41, 303 (1954).
5. 4) Cf. R. B. Moffett, J. E. Stafford, J. Linsk, and W. M. Hoehn: J. Am. Chem. Soc., 68, 1857 (1946).