Stewart, Ross published the artcileStrongly basic systems. IV. Substituent effects on the acidity of aromatic amines, Quality Control of 1821-27-8, the publication is Canadian Journal of Chemistry (1964), 42(7), 1694-8, database is CAplus.
The effect of ring substituents on the acidity of anilines and diphenylamines is examined In general the effects are similar to those found in the analogous ionization of phenols. The acidities of diphenylamines having 2 or 3 nitro groups in one ring and variable substituents in the other ring can be correlated by the Hammett relation. A good correlation is found between the acidities and basicities of aromatic amines, although basicity is more sensitive to the presence of ring substituents than is acidity. The relation of these results to the general question of 1st and 2nd dissociation constants of dibasic acids is considered.
Canadian Journal of Chemistry published new progress about 1821-27-8. 1821-27-8 belongs to catalysis-chemistry, auxiliary class Nitro Compound,Amine,Benzene, name is Bis(4-nitrophenyl)amine, and the molecular formula is C17H18N3NaO3S, Quality Control of 1821-27-8.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia