| Abstract: | Diazotization of 2-nitro-4-(4-pyridinyl)aniline ( 4 ) in hydrobromic acid gave the corresponding bromo derivative 5 which was treated with cuprous cyanide to give the benzonitrile derivative 6 which in turn was converted to 2-nitroacetophenone derivative 9 . Reduction of 9 followed by diazotization of the resulting amine 10 gave 7-(4-pyridinyl)cinnolin-4(1H)-one ( 11 ) which was subsequently converted to 1 -ethyl-1,4-dihydro-4-oxo-7-(4-pyridinyl)cinnoline-3-carboxylic acid ( 14 ) in three steps. |
