Synthesis, crystal structure and DNA-binding studies of the Ln(III) complex with 6-hydroxychromone-3-carbaldehyde benzoyl hydrazone

• Published in: Journal of inorganic biochemistry Vol. 101; no. 10; pp. 1492 - 1504
• Main Authors: Wang, Bao-dui, Yang, Zheng-Yin, Crewdson, Patrick, Wang, Da-qi
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2007
• Subjects: 6-Hydroxy chromone-3-carbaldehyde benzoyl hydrazone; Antioxidants - chemistry; Cell Line, Tumor; Chromones - chemistry; Crystal Structure; Crystallography, X-Ray; DNA - chemistry; DNA binding; Humans; Hydrazones - chemistry; Lanthanoid Series Elements - chemistry; Models, Molecular; Molecular Structure; Rare earth complexes; Spectrometry, Fluorescence; Spectrometry, Mass, Fast Atom Bombardment; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Crystal Structure; Rare earth complexes; 6-Hydroxy chromone-3-carbaldehyde benzoyl hydrazone; DNA binding
• ISSN: 0162-0134; 1873-3344
• DOI: 10.1016/j.jinorgbio.2007.04.007

A novel 6-hydroxy chromone-3-carbaldehyde benzoyl hydrazone ligand ( L) and its Ln(III) complexes, [Ln = La( 1) and Sm( 2)], have been prepared and characterized. The crystal and molecular structures of complexes 1 and 2 were determined by single-crystal X-ray diffraction. Antioxidative activity tests in vitro showed that L and its complexes have significant antioxidative activity against hydroxyl free radicals from the Fenton reaction and also oxygen free radicals, and that the effect of the La(III) complex 1 is stronger than that of mannitol and the other compounds. The compounds were tested against tumor cell lines including HL-60 and A-549. The data shows that the suppression rate of complexes 1 and 2 against the tested tumor cells are superior to the free ligand ( L). The interactions of complexes 1 and 2, and L, with calf thymus DNA were investigated by UV–visible (UV–vis), fluorescence, denaturation experiments and viscosity measurements. Experimental results indicated that complexes 1 and 2, and L can bind to DNA via the intercalation mode, and that the binding affinity of complex 1 is higher than that of complex 2 and of free ligand ( L). The intrinsic binding constants of complexes 1 and 2, and L were (7.62 ± 0.56) × 10 6, (3.70 ± 0.47) × 10 6 and (2.41 ± 0.46) × 10 6 M −1, respectively.