Synthesis, structure and antitumor activities of a new macrocyclic ligand with four neutral pendent groups: 1,4,7,10-tetrakisbenzyl-1,4,7,10-tetraazacyclododecane (L) and its Co, Ni and Cu complexes
Dy. Kong et al., Synthesis, structure and antitumor activities of a new macrocyclic ligand with four neutral pendent groups: 1,4,7,10-tetrakisbenzyl-1,4,7,10-tetraazacyclododecane (L) and its Co, Ni and Cu complexes, TRANSIT MET, 24(5), 1999, pp. 553-557
A new macrocyclic ligand, 1,4,7,10-tetrakisbenzyl-1,4,7,10-tetraazacyclodod
ecane (L) and its three new divalent metal complexes of general formula: M(
NO3)(2)(L)nH(2)O [M = Co(1), Ni(2), n = 0; M = Cu(3), n = 1.5] have been sy
nthesized and characterized by elemental analysis, i.r., EI mass spectra an
d molecular conductance. Complex (2) has been characterized by X-ray diffra
ction. In complex (2), the central (NiI)-I-I atom coordinatively bonds to f
our nitrogen atoms of the macrocyclic ligand and two oxygen atoms of nitrat
e anion, to form a distorted octahedron. X-ray diffraction indicated that t
he bonds Ni-N(1), Ni-N(2), Ni-N(3) and Ni-N(4) are of almost equal length,
i.e. 2.11(1), 2.12(1), 2.10(1) and 2.17(1) Angstrom, respectively. Bond len
gths of Ni-O(1) and Ni-O(2) are 2.11(1) and 2.10(1) Angstrom. Preliminary p
harmacological tests show that these complexes have high antitumor activity
towards HL-60 tumor cell lines.