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Abstract
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Two potentially N 6 O 2 macroacyclic Schiff base ligands (H 2 L 1 and H 2 L 2 ) were derived from the condensation of a new polyamine, 2,2 -(4,4 -(propane-1,3-diyl)bis(piperazine-4,1-diyl)) diethanamine (A), with 2-Hydroxy- benzaldehyde or 2-hydroxy-3-methoxybenzaldhyde respectively. In the presence of appropriate metal ions, six manganese (II), zinc (II) and cadmium (II) macroacyclic Schiff-base complexes were obtained. All products were characterized by elemental analysis, mass spectrometry and FT-IR, 1 H and 13 C NMR. Competitive 7 Li NMR measurements were employed to monitor the stability of Cd 2 + , Zn 2 + and Mn 2 + ions complexes with H 2 L 1 and H 2 L 2 Ligands in methanol and acetonitrile separately. The variation of 7 Li chemical shift with [H 2 L]/[M 2 + ] mole ratios indicated the formation of 1:1 complexes. The formation constants of the resulting complexes were found to be in the order M 2 + -H 2 L 1 > M 2 + -H 2 L 2 and Cd 2 + -H 2 L > Zn 2 + -H 2 L > Mn 2 + -H 2 L. The resulting complexes are more stable in acetonitrile than in methanol. The cytotoxic properties of complexes were studied.
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