Abstract 2-Isonicotinoylacetophenone (1) reacts with aqueous ammonia in the presence of acid to produce the deep blue 3-(4-pyridyl)-1-[3-(4-pyridyl)-1H-1-isoindolylidenemethyl]-2H- isoindole which changed to the deep bluish green adduct showing the wavelength maximum at 744 nm by treating with methyl iodide. From the reaction of 1 and glycine or its methyl ester the red 3, 3′-di-(4-pyridyl)-1, 1′-vinylenebis (2H-2-isoindoleacetic acid) or ...
