Ag/SiO₂/Fe₃O₄@GO as a Recyclable Catalyst Promoted Green Synthesis of Novel Pyrimidoazepines via Multicomponent Reaction of Isatins Employing

ABSTRACT This investigation scrutinized the utilization of a complex methodological framework involving isatins, electron‐deficient acetylenic derivatives, α‐haloketones, and guanidine within an aqueous medium at room temperature, propelled by Ag/SiO 2 /Fe 3 O 4 @Graphene oxide. The principal aim was to synthesize innovative pyrimidoazepine compounds with significant yields. The resulting pyrimidoazepines are characterized by the presence of NH functional groups exhibiting acidic protons and demonstrate pronounced antioxidant activities. The (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) MTT assay was utilized to evaluate the cytotoxicity of all synthesized compounds in vitro against neoplastic cell lines (MCF‐7 and A549) in addition to nonmalignant cell lines (BEAS‐2B). Cytotoxicity is delineated as the ability of a compound to provoke cellular mortality. The derivative 5e was recognized as the most formidable cytotoxic agent, showcasing a lack of selectivity akin to that of doxorubicin. In contrast, compound 5b may be considered as exhibiting comparable efficacy but with increased selectivity in relation to doxorubicin. The employed methodology for the synthesis of pyrimidoazepines presents numerous advantages, encompassing expedited reaction kinetics, outstanding product yield, and streamlined product isolation.