M. Shabbir, Z. Akhter, I. Ahmad
Jul 15, 2016
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Influential Citations
35
Citations
Journal
Journal of Molecular Structure
Abstract
Abstract Four novel ON donor Schiff bases (E)-2-((4-phenoxyphenylimino)methyl)phenol (HL1), (E)-2-((4-(4-biphenyloxy)phenylimino)methyl)phenol(HL2), (E)-2-((4-(naphthalen-1-yloxy) phenylimino)methyl)phenol(HL 3 )and(E)-2-((4-(2-naphthoxy)phenylimino)methyl)phenol (HL 4 )have been synthesized and characterized by various spectroscopic, analytical and electro-analytical techniques. Single crystal X-ray diffraction analysis of Schiff base (HL 3 ) revealed that phenol and anthracene rings are inclined at 30.25(9)° and 89.64(4)° to the central phenyl ring, respectively. Intra and inter molecular interactions are observed in single crystal analysis of HL 3 Intramolecular interactions are hydrogen bonding but most of the intermolecular interactions are of the C–H … π type. There is a bit of π … π stacking between the anthracene groups. Only compounds (HL 1 ) and (HL 3 ) have been investigated for the biological activities due to slight solubility of (HL 2 ) and (HL 4 ) in DMSO. The results of brine shrimp cytotoxicity assay indicated LD 50 values 50 values 14.20 and 4.54 μg/ml respectively. The compounds were highly active in protecting DNA against hydroxyl free radicals in concentration dependent manner. Voltammetric results indicated that one electron irreversible oxidation product is formed due to hydroxyl moiety and the process is diffusion controlled. On exposing to DNA environment the electrooxidised product developed electrostatic linkage and groove binding intercalation while consuming the DNA concentration substantially. The binding strength was quantitative in terms of drug-DNA binding of the order of 10 4 M −1 .