Two
new neutral dimer Cadmium(II) complexes, [Cd2(dmdphphen)2X4] and where X
= Cl (complex 1), Br (complex 2), and dmdphphen =
2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, were synthesized and
characterized by an elemental analysis, UV-Vis, IR, TG/DTA, CV and
single crystal X-ray diffraction. Complex 1 crystallizes in the
triclinic system with the space group P-1 with unit cell parameters a =
10.1124(8) Å, b = 10.8875(8) Å, c = 11.5730(9) Å, α = 108.323(3)º, β =
107.010(3)º, γ = 91.260(3)º V = 1147.51(15) Å3 and Z = 1. The Cd(II)
ions are located in a slightly distorted square-pyramidal geometry. The
complexes exhibit a quasi-reversible one electron response at -570 mV
vs. Cp2Fe/Cp2Fe+ , which has been assigned Cd(II)/Cd(III) couples.
TG/DTA result shows that these complexes are very stable and decomposed
through one step reaction. Calcination of Complex 1, revealed the
formation of Cubic nanoparticle CdO.
Aggregated states have been alluded to for many DNA minor groove binders but details of the molecule-on-molecule relationship have either been under-reported or ignored. Here we report our findings from ITC and NMR measurements carried out with AIK-18/51, a compound representative of the thiazotropsin class of DNA minor groove binders. The free aqueous form of AIK-18/51 is compared with that found in its complex with cognate DNA duplex d(CGACTAGTCG)2. Molecular self-association of AIK-18/51 is consistent with anti-parallel, face-to-face dimer formation, the building block on which the molecule aggregates. This underlying structure is closely allied to the form found in the ligand's DNA complex. NMR chemical shift and diffusion measurements yield a self-association constant Kass = (61 ± 19) × 103 M− 1 for AIK-18/51 that fits with a stepwise self-assembly model and is consistent with ITC data. The deconstructed energetics of this assembly process are reported with respect to a design strategy for ligand/DNA recognition.
Two tetrahedral mononuclear complexes with a general formula
[CoX2(dmphen)](1-2) (where dmphen is 2,9-dimethyl 1,10-phenanthroline and 1 (X=Br), 2 (X=NCS)) have been
synthesized. These complexes are characterized by elemental analysis, IR, UV-visible, TG/DTA and
by X-ray diffraction.The calculated electrostatic potential surface of 2 has shown that the
electrostatic potential values
around sulfur atom is anistropically distributed; the potential values along
C-S bond is less negative -region of S atom. This agrees with the observed geometricalpthan
the corresponding values in the .°arrangement
of C-H…S-C hydrogen bonding interactions, the avg. of H…S-C angle is 81
Antimicrobial properties of cobalt (II) complexes was also assessed. Cobalt
complexes exhibited significant antibacterial activity against different Gram negative and positive
human pathogens. The absorption spectrum of these complexes in acetone was modeled by time-dependent
density functional
theory (TD-DFT).