Unraveling the structure–activity relationships of organometallic ferrocene-pyrazole and ferrocene-pyrimidine curcumin analogues in amyloid-β aggregation and glioblastoma treatment

Neurodegenerative and oncological disorders, such as Alzheimer's disease (AD) and glioblastoma (GBM), are major global health challenges. Recent evidence indicates shared molecular mechanisms between these diseases, including dysregulated oxidative stress, mitochondrial dysfunction, and protein aggregation. We hypothesized that ferrocene-containing curcumin derivatives could exert dual-functional effects by simultaneously modulating amyloid-β (Aβ) aggregation and inhibiting glioblastoma cell proliferation. This study explores organometallic ferrocene compounds linked to four pyrazole and two pyrimidine analogues of curcumin with different substituents for their effects on amyloid-β-peptide (Aβ) aggregation and glioblastoma. To test this, pyrazole (FcPy-Cur-H, FcPy-Cur-COPh, FcPy-Cur-COFc, FcPy-Cur-Me) and pyrimidine (FcPyn-Cur-O, FcPyn-Cur-S) analogues were synthesized and evaluated. Thioflavin T fluorescence, atomic force microscopy, and single-molecule localization microscopy revealed structure-dependent inhibition of Aβ fibrillogenesis, with FcPyn-Cur-O, FcPyn-Cur-S, and FcPy-Cur-H showing the strongest anti-amyloidogenic activity. Concurrently, these derivatives reduced U87MG glioblastoma cell viability in a dose-dependent manner, inducing apoptotic features, mitochondrial disruption, and α-tubulin destabilization. Our results demonstrate that specific structural modifications of ferrocene-curcumin analogues enhance their dual anti-amyloidogenic and anticancer activities, highlighting the therapeutic potential of multifunctional compounds. This study provides a conceptual advance by combining neurodegenerative and oncological targets within a single chemical framework, offering a promising strategy for the development of multitargeted therapeutics for complex brain disorders.