Fundamental Studies on Clinical Chemistry. VII. Janovsky Reaction of Polynitrodiphenyl Compounds

This work was undertaken to obtain a more satisfactory reagent for the assay of active methylene compounds than has been used. Biphenyl, diphenylmethane, diphenyl ether, diphenyl sulfide, diphenylsulfone and stilbene with nitro groups in 4, 4'-, 2, 4-, 2, 2', 4, 4'-positions were prepared and their color reactions with acetone and cyclohexanone in the presence of alkali were examined. 4, 4'-Dinitro compounds gave negative Janovsky reaction. Bis(p-nitrophenyl)-(IV) and bis(2, 4-dinitrophenyl)methane (V) gave blue color in methylcellosolve with addition of alkali without active methylene compound. 2, 4-Dinitro compounds showed bathochromic shift as compared with usual reagents such as m-dinitrobenzene, 1, 3, 5-trinitrobenzene and picric acid. The intensities of colors by these reagents were lower. 2, 2', 4, 4'-Tetranitro compounds showed higher intensities and sufficient stabilities of the color produced, but no bathochromic shifts. These tetranitro compounds also gave the specific color reactions for active methylene compounds such as acetone, cyclohexanone, 17-ketosteroids, creatinine and cardiac glycosides. 2, 2', 4, 4'-Tetranitrobiphenyl (III) could be the reagent that has higher sensitivity, sufficient stability and specificity in color reaction of active methylene compounds with alkali.