In this study, 2,5-dimethyl-4-((4-nitrobenzylidene) amino) phenol (A1), N,N'-([1,1'-biphenyl]-4,4'-diyl)bis(1-(2,4-dimethoxyphenyl)methanimine (A2) and 4,4'-(([1,1'-biphenyl]-4,4'-diylbis(azaneylylidene))bis (methaneylylidene))bis(2-methoxyphenol) (A3) were synthesised. Analytical studies were then carried on (A1), (A2) and (A3); the results of the solvent effect were displayed that the best solubility was in ethanol and DMSO of each, which is due to the fact that the effect of the dielectric constant is the main factor that can control the shift of the absorption beaks. The results were also indicated, that there is a slight deviation from the linear relationship in (A3) that may have related to the hydrogen bond between this base and the solvent. However, the results of the pH effect of (A1), (A2) and (A3) in a range of buffer solution were gave two isopiestic points just in (A3). Due to the ionization constant (pKa) and the protonation constant (pKp) were calculated by using the half height method. Further, the results were indicated the existence of the equilibrium schemes of which displays the suggested ionization of (A3) in acidic and basic medium. Further, the effect of the prepared Schiff bases (A1, A2, and A3) were studied on breast cancer cells type MCF-7 using five different concentrations of each. The results were showed high inhibition activities of each especially at high concentration, due recommend these bases as novel anti-cancer drugs.