Synthesis, characterization and in vitro DNA binding studies of tin(IV) complexes of tert-butyl 1-(2-hydroxy-1-phenylethylamino)-3-methyl-1-oxobutan-2-yl carbamate
作者:Farukh Arjmand、Jamsheera A.
DOI:10.1016/j.jorganchem.2011.08.009
日期:2011.11
Tin(IV) complexes 1(a and b) and 2(a and b) of valine derived peptide derivatives were synthesized and characterized on the basis of elemental analysis, IR, (1) H, C-13, Sn-119 NMR, ESI-MS spectra and molar conductance measurements. The C-Sn-C angle was estimated from C-I3 and H-1 NMR data (1)J(Sn-119, C-I3) = 623 Hz; solution (2)J(Sn-119, H-1) = 93.04 Hz to be 149.9 degrees. In vitro binding studies of complexes 1 and 2 under physiological conditions at room temperature with CT-DNA were carried out employing UV-visible, fluorescence, circular dichroism and viscometric studies. The binding affinity of the complexes was quantified by calculating the K-b values and it follows the order 2a > 1a > 2b > 1b. To further examine the specific mode of binding, the interaction of complexes 2(a and b) were carried out with 5'GMP and 5'TMP by using absorption and NMR (H-1, P-31) spectroscopy. The supercoiled pBR322 plasmid DNA cleavage activity of the complexes was ascertained by gel electrophoresis assay. The complexes cleave supercoiled pBR322 plasmid DNA efficiently into its nicked form at micromolar concentrations. (C) 2011 Elsevier B. V. All rights reserved.