Multifunctional characterization of a novel Schiff base (E)-4-nitro-2-((pyridin-4 ylmethylene)amino)aniline (NPD-PC): Crystal engineering, thermal stability, antimicrobial activity and cytotoxicity

A novel Schiff base, (E)-4-nitro-2-((pyridin-4-ylmethylene)amino)aniline(NPD-PC), was synthesized and characterized using FT-IR, UV–Vis, and 1 H NMR spectroscopy, along with single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system with space group I2/a, and its optimized geometry, HOMO-LUMO and Mulliken charge analyses was calculated by DFT studies at the B3LYP/6-311G(d,p) level. Crystal packing is stabilized by strong N–H•••N and weak C–H•••O hydrogen bonds, together with π–π stacking and C–H•••π interactions, while Hirshfeld surface analysis confirmed these non-covalent interactions, with 2D fingerprint plots showing dominant contributions from H•••H and O•••H/H•••O contacts. Thermogravimetric analysis revealed that the compound undergoes single-step decomposition with a stable residue at 248 °C, demonstrating good thermal stability. The results indicated that NDP-PC exhibits potential antibacterial activity against gram-negative bacterial strains and the cytotoxic effect was significantly inhibited against the MCF cell line at 100 μl. The MEP surface, Mulliken charge distribution and HOMO–LUMO energy gap (2.7350 eV) indicated high electronic stability and significant reactive potential. In silico ADME profiling further predicted good oral bioavailability along with favorable drug-like characteristics. Collectively, these findings suggest that the schiff base possesses promising applications in both medicinal and material sciences. • A novel Schiff base NPD-PC was synthesized and structurally validated through experimental characterization and DFT analysis, confirming its stable electronic framework. • The compound displayed strong antibacterial efficacy and notable cytotoxicity against MCF-7 breast cancer cells, demonstrating dual biological potential. • DFT-derived HOMO–LUMO gap (2.7350 eV) revealed optimal charge transfer and favorable electronic stability. • In silico ADME and molecular docking studies indicated excellent oral bioavailability and receptor-specific interactions. • NPD-PC exhibited strong binding affinity toward estrogen, progesterone and EGFR receptors, highlighting its multitarget therapeutic potential.