1. 1) Paper read before the Tohoku Local Meeting of the Chemical Society of Japan in Akita, Oct. 2, 1953.
2. 2) T. Nozoe, T. Mukai, K. Takase, and T. Nagase: Proc. Japan Acad., 28, 477 (1952).
3. 3) Cf. report on the reaction product of 2-halotropones and thiourea. T. Nozoe, M. Sato, and K. Matsui: Sci. Repts. Tohoku Univ., First Series, 37, 211 (1953).
4. 4) Microanalyses were carried out by Mr. Kawamoto of Sankyô Co., Ltd., and Miss K. Katô of this Laboratory. The Compounds of this series generally have high melting points and their combustion is attended with difficulty.
5. 5) Imidazole nucleus is known to be fairly stable against hydrogenaticn. Cf. Chem. Rev., 48, 319 (1951).