Synthesis, Crystal Structure, and Urease Inhibitory Activity of an Unexpected Binuclear Zinc(II) Complex With Schiff Base Ligand

An unexpected binuclear zinc Schiff base complex C1 [Zn 2 (HL) 2 (Bipy) 2 ] (HL = (S,E)‐2‐((3,5‐dichloro‐2‐hydroxy‐benzylidene)amino)‐3‐phenylpropanoic acid) was synthesized and characterized by single‐crystal X‐ray diffraction,elemental analysis, and further confirmed by 1 H NMR, UV–vis and IR spectroscopy, which verified the structural integrity and homogeneity of the bulk sample. The results reveal that the complex belongs to the monoclinic crystal system with the P21/c space group, and its crystallographic parameters are determined as a = 12.1231(6), b = 31.2765(18), c = 15.6384(8) Å, α = 90°, β = 106.517(2)°, γ = 90°, and unit cell volume V = 5684.9(5) Å 3 . In the molecular structure, two asymmetric Zn(II) centers are bridged by carboxylate oxygen atoms, forming a stable Zn 2 ─O structural skeleton. HSA demonstrates that the crystal packing and supramolecular framework stability are mainly dominated by intermolecular H─H van der Waals interactions, Cl─H halogen hydrogen bonds and O─H hydrogen bonds. Density functional theory calculations verify that the complex possesses a narrow HOMO–LUMO energy gap (Δ E = 3.114175 eV), indicating favorable electron transfer and reactivity. In vitro urease inhibition assays indicate that the prepared binuclear zinc complex exhibits prominent urease inhibitory activity with an IC 50 value of 9.01 ± 0.274 μM, which is much lower that of the positive control AHA (IC 50 = 54.59 ± 0.69 μM). Molecular docking studies of C1 with jack bean urease (PDB: 3LA4) further revealed a plausible binding mode of the complex within the enzyme active site, highlighting the roles of the metal center and the coordinated ligands in urease recognition. This study provides a feasible design strategy and experimental basis for the development of high‐efficiency urease inhibitory metal complexes.