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In this study, we examined the interaction process of human serum albumin (HSA) with a water‐soluble zinc(II) complex of dichloro {2‐[N‐(2‐hydroxyethylammonioethyl) imino methyl] phenol} at pH=7.4 and in vitro utilizing molecular docking modeling and spectral techniques. In the multi‐temperature fluorescence test, the consecutive and gradual addition of the zinc(II) complex to the HSA‐containing cell resulted in fluorescence quenching, and it showed that the zinc(II) complex‐protein interaction is associated with a static quenching mechanism; also, the number of binding sites (n) and the binding constant (Kb) were computed by this test. The evaluation of thermodynamic data showed spontaneous progression, and the involvement of hydrogen bonding/van der Waals forces in protein‐zinc(II)complex formation. The site markers competition studies using two drugs, warfarin and ibuprofen, indicated that zinc(II) complex binds to the protein via site I/sub‐domain IIA. The albumin‐zinc(II) complex interaction and the structural alterations in the serum albumin were proved by electronic absorption technique and circular dichroism spectroscopy. Job′s curve exhibited a stoichiometric ratio of 1 : 1 in the HSA‐zinc(II) complex adduct. The accuracy of the results obtained from experimental findings on the interaction between HSA and zinc(II) complex was checked by molecular docking simulation, which illustrated a good agreement between experimental and theoretical data. [ABSTRACT FROM AUTHOR]

Two lead(II) complexes of 5,6‐bis(furan‐2‐yl)‐3‐(pyridin‐2‐yl)‐1,2,4‐triazine (DFPT), namely one‐dimensional (1D) catena‐poly[[bis[5,6‐bis(furan‐2‐yl)‐3‐(pyridin‐2‐yl‐κN)‐1,2,4‐triazine‐κN2]lead(II)]‐di‐μ‐thiocyanato‐κ2N:S;κ2S:N], [Pb(NCS)2(C16H10N4O2)2]n, 1, and binuclear di‐μ‐dicyanamido‐κ2N1:N5;κ2N5:N1‐bis{[5,6‐bis(furan‐2‐yl)‐3‐(pyridin‐2‐yl‐κN)‐1,2,4‐triazine‐κN2](nitrato‐κ2O,O′)lead(II)}, [Pb2(C2N3)2(NO3)2(C16H10N4O2)4], 2, as well as DFPT itself, were prepared and identified by elemental analysis, FT–IR, 1H NMR spectroscopy and single‐crystal X‐ray structural analyses. In the double‐chain 1D coordination polymer of 1 and the binuclear structure of 2, the Pb atom has a hemidirected‐PbN6S2 and a rare holodirected‐PbN6O2 environment, respectively, with a distorted cubic geometry. All the coordination modes of dicyanamide ligands within lead complexes were studied using the Cambridge Structural Database (CSD) to compare them with the structures of 1 and 2. In addition to hydrogen bonds, the crystal networks are stabilized by π–π stacking interactions between the triazine, furyl and pyridine aromatic rings. The most stable theoretical structures of the title compounds predicted by density functional theory (DFT) calculations were compared with the solid‐state results. [ABSTRACT FROM AUTHOR]

The reaction between 2‐[2‐(aminoethyl)amino]ethanol and pyridine‐2‐carbaldehyde in a 1:2 molar ratio affords a mixture containing 2‐({2‐[(pyridin‐2‐ylmethylidene)amino]ethyl}amino)ethanol (PMAE) and 2‐[2‐(pyridin‐2‐yl)oxazolidin‐3‐yl]‐N‐(pyridin‐2‐ylmethylidene)ethanamine (POPME). Treatment of this mixture with copper(II) chloride or cadmium(II) chloride gave trichlorido[(2‐hydroxyethyl)({2‐[(pyridin‐2‐ylmethylidene)amino]ethyl})azanium]copper(II) monohydrate, [Cu(C10H16N3O)Cl3]·H2O or [Cu(HPMAE)Cl3]·H2O, 1, and dichlorido{2‐[2‐(pyridin‐2‐yl)oxazolidin‐3‐yl]‐N‐(pyridin‐2‐ylmethylidene)ethanamine}cadmium(II), [CdCl2(C16H18N4O)] or [CdCl2(POPME)], 2, which were characterized by elemental analysis, FT–IR, Raman and 1H NMR spectroscopy and single‐crystal X‐ray diffraction. PMAE is potentially a tetradentate N3O‐donor ligand but coordinates to copper here as an N2 donor. In the structure of 1, the geometry around the Cu atom is distorted square pyramidal. In 2, the Cd atom has a distorted octahedral geometry. In addition to the hydrogen bonds, there are π–π stacking interactions between the pyridine rings in the crystal packing of 1 and 2. The ability of PMAE, POPME and 1 to interact with ten selected biomolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS, Top II and B‐DNA) was investigated by docking studies and compared with doxorubicin. [ABSTRACT FROM AUTHOR]