| 摘要 |
553,506. Pyrazolone derivatives. KODAK, Ltd. (Eastman Kodak Co., Porter, H. D., Vittum, P. W., and Weissberger, A.). Nov. 20, 1941, No. 14935. Drawings to Specification. [Class 2 (iii)] [Also in Group XX] 1 - (2<SP>1</SP> - Benzthiazolyl) - 3 - hydroxy - 5 - iminopyrazolone is prepared by refluxing together ethylcyanoacetate and 2 - benzthiazolylhydrazine in the presence of sodium ethylate and acidifying, or by adding cyanoacetamide to a solution of 2-benzthiazolylhydrazine in dioxane to give #-cyanoacetyl-2- benzthiazolylhydrazine and refluxing the latter in sodium methylate solution and acidifying. 1 - (α - quinolinyl) - 3 - - hydroxy - 5 - imino - pyrazolone and 1 - (α - pyridinyl) - 3 - hydroxy - 5 - iminopyrazolone also used as couplers in colour photography are similarly prepared. |
