Synthesis and X‐Ray Structural Analyses Combined Anticancer Efficacy and Molecular Docking for N‐Aryl‐(2‐pyridyl)aldimines

Abstract

The reaction of 2‐amino‐4,6‐dimethylpyridine with 4‐cyanobenzaldehyde, salicylaldehyde or 2‐hydroxy‐1‐naphthaldehyde furnished the corresponding N‐aryl‐(2‐pyridyl)aldimines in very good yields. The synthetised Schiff bases were characterized by FT‐IR, 1H, 13C, DEPT‐135 and [1H,13C]‐HSQC NMR spectroscopy, HRMS and elemental analyses. Additionally, the structure of 2‐((E)‐(4,6‐dimethylpyridin‐2‐ylimino)methyl)phenol was unambiguously determined by single crystal X‐ray diffraction analysis. Hirshfeld analysis of molecular packing was performed. The most common intermolecular interaction is the hydrogen‐hydrogen (56.8 %) contacts while the most significant interactions are the O…H (6.5 %) and C…C (4.2 %) contacts. DFT calculated geometric parameters and NMR chemical shifts are well correlated with the experimental data. This compound has a net dipole moment of 2.4261 Debye. The MCF‐7 growth was suppressed by N‐aryl‐(2‐pyridyl)aldimines more than that for T47D cell line. The IC50 values of 4‐((E)‐(4,6‐dimethylpyridin‐2‐ylimino)methyl)benzonitrile against MCF‐7 and T47D cell lines were the lowest and it is considered the most promising candidate as anticancer agent. Furthermore, this study conducted a molecular docking of benzonitrile‐based Schiff base onto DNA duplex to explore a potential molecular mechanism for the robust anticancer activities of this Schiff base adduct. The molecular docking results indicate that benzonitrile‐based Schiff base exhibits characteristics of a potential DNA minor groove binder.