Synthesis and characterization of new 13 and 14-membered macrocycles and their transition metal complexes.

Autor: Nahid Nishat, Rahis-ud-din, Mohammad M. Haq, Khwaja S. Siddiqi
Zdroj: Transition Metal Chemistry; Nov2003, Vol. 28 Issue 8, p948-953, 6p
Abstrakt: Two new macrocyclic ligands 1,4,7,9,12-pentaaza-10,11-dioxo-8,9,12,13-bis-(1'-oxo-3'-thio-2'-hydropyrimidine)-trideca-7,13-diene, (L1) and 1,4,7,9,12-pentaaza-10,12-dioxo-8,9,13,14-bis-(1'-oxo-3'-thio-2'-hydropyrimidine)-tetradeca-7,14-diene, (L2) and their complexes with CrIII, MnII, FeIII, CoII, NiII, CuII and ZnII have been synthesized, and characterized by elemental analysis, i.r., 1H-n.m.r., e.p.r., u.v.–vis. spectroscopy, magnetic susceptibility and conductance measurements. The conductivity measurements suggest that the complexes of divalent metal ions are 1:1 electrolytes whereas the trivalent metal ions are non-electrolytes. On the basis of electronic spectra and magnetic moment measurements the CrIII and FeIII complexes are octahedral, while the divalent metal complexes are tetrahedral except for the NiII and CuII complexes which are proposed to have square planar geometry. All the ligands and their complexes have been screened against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria E. coli. The results show that they inhibit the growth of bacteria. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index