Synthesis, Crystal Structure, DFT Calculations, Hirshfeld Surface Analysis, and Anticancer Effect of Ethyl 2‐(3‐methyl‐11‐oxo‐10,11‐dihydro‐5 H ‐dibenzo[1,5] diazepin‐1‐yl) Acetate

In this study, we explored the synthesis and characterization of ethyl 2‐(3‐methyl‐11‐oxo‐10,11‐dihydro‐5 H ‐dibenzo[1,5]diazepin‐1‐yl) acetate. The compound was synthesized via refluxing ( Z )‐4‐(2‐oxopropylidene)‐1,5‐benzodiazepin‐2‐one with N ‐(1‐naphthyl)ethylenediamine dihydrochloride in ethanol, followed by recrystallization. Density functional theory (DFT) calculations using the B3LYP/6–311(d,p) level of theory provided insights into the molecular structure and reactivity, supported by Hirshfeld surface analysis. X‐ray crystallography confirmed the monoclinic crystal system and detailed the molecular geometry. The antiproliferative activity was assessed using the MTT assay against several cancer cell lines. Our findings indicate significant intermolecular interactions, notably hydrogen bonding, which are crucial in the compound's crystalline arrangement. The study's results highlight the potential of compound 3 as a medicinally significant molecule due to its chemical reactivity and biological activity. These insights contribute to understanding the structure‐activity relationship in diazepine derivatives, offering a foundation for future therapeutic applications. The antiproliferative activity of 3 demonstrated a superior anticancer effect against three cancer cell lines. Lastly, the molecular docking study showed good binding interactions between 3 and the active sites of EGFR and HER2 protein kinase enzymes.