N. Gokhale et al., The crystal structure of first copper(II) complex of a pyridine-2-carboxamidrazone - a potential antitumor agent, INORG CH C, 4(1), 2001, pp. 26-29
The crystal structure of the neutral, distorted square planar copper(II) co
mplex, viz. cis-[dichloro (N'-(2-benzyloxybenzylidene) pyridine-2-carboxami
drazone) copper(II)] (1) is reported which is the first well-characterized
copper(II) complex of the series (space group C2/c, a = 18.414(5) Angstrom;
b = 8.6510(10) Angstrom; c = 27.091(4) Angstrom; alpha = 90 degrees; beta
= 109.800(17)degrees; gamma = 90 degrees; R-1 = 0.0331 wR(2) = 0.0852). The
distortion from square planar geometry is thought to arise from the non-eq
uivalent ligand donor set. The Cu-Cl bonds are equivalent with one of the C
l atoms making intermolecular contact at 2.6070 Angstrom with adjacent copp
er rendering a pseudo-square pyramidal geometry around copper. The complex
is further characterized by UV/VIS spectroscopy, electrochemistry and magne
tic susceptibility measurements. The in vitro antitumor activity of this co
mplex and the parent ligand is determined against the human breast cancer c
ell-line MCF-7 which revealed that copper complexation renders a highly ant
iproliferative compound with IC50 value of 3 muM. (C) 2001 Elsevier Science
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