2-s-Butyl-, 2-t-butyl-, and 2, 7-di-t-butyl-9-aminoacridine, and other acridines, have been synthesised from the corresponding 2-carboxydiphenylamines (diphenylamine-2-carboxylic acids). Their 1H nmr spectra have shown that earlier assignments made for 9-aminoacridine must be revised. The nmr spectra for intermediates in the syntheses show a steric effect for the t-butyl group and indicate the presence of geometric and rotational isomers of the ...
