Rahim_2025_Z.Naturforsch.C.J.Biosci__

A new unusual C-methylated chalcone was successfully isolated from the leaves of Syzygium dyerianum (King) Chantaran. & J.Parn, identified as syzydyerin A (1), together with beta-sitosterol, friedelin and lupeol. The characterisation and structural elucidation of the isolated compounds were established by extensive spectroscopic data analysis and comparison with literature data. Compound 1 exhibited inhibitory activity against acetylcholinesterase (AChE) and lipoxygenase (LOX) with IC50 values of 50.4+/-0.2 microm and 30.7+/-0.25 microm, respectively, compared to the reference inhibitors galantamine (IC50=40.7+/-0.12 microm) for AChE and quercetin (IC50=3.5+/-0.13 microm) 5-LOX. Molecular docking analysis revealed that compound 1 exhibits strong binding affinities toward AChE (-11.0 kcal/mol) and 5-LOX (-9.1 kcal/mol), comparable to standard inhibitors, with key Pi-Pi stacking and hydrogen bonding interactions stabilizing its binding at both active sites, highlighting its promising dual inhibitory potential. The study underscores the value of S. dyerianum as a source of bioactive compounds with potential applications in treating neuroinflammatory diseases.