| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1338144 | Polyhedron | 2011 | 6 Pages |
Two new isomorphous tetranuclear complexes [Cu4L2(4,4′-bipy)2]·(ClO4)4·2CH3CN·2H2O (1) and [Zn4L2(4,4′-bipy)2]·(ClO4)3·CH3O·4H2O (2) have been obtained and fully characterized (where bipy = bipyridine, H2L = macrocycle is the [2+2] condensation product of 2,6-diformyl-4-fluoro-phenol and 1,4-diaminobutane). They exhibit wheel-like configuration in which two 4,4′-bipy molecules connect two dinuclear [M2L]2+ units. The interactions of the complexes with calf thymus DNA were studied by UV–Vis and CD spectroscopic techniques. The binding constants of 1 and 2 are 2.27 × 106 and 3.89 × 105 M−1, respectively. The magnetic measurement of 1 reveals that there are strong antiferromagnetic coupling (J = –272.6 cm−1) between two Cu(II) ions in the macrocyclic unit and ferromagnetic interaction (j′ = 41.7) between the Cu(II) ions in two adjacent macrocyclic units. Furthermore, the cyclic voltammogram of 1 shows that it undergoes two quasi-reversible processes with the half wave potentials –0.232 and –0.606 V, respectively.
Graphical abstractTwo new isomorphous wheel-like tetranuclear complexes have been obtained by template reaction. The interactions of the complexes with calf thymus DNA were studied by UV–Vis and CD spectroscopic techniques. The mechanism for DNA cleavage reaction by copper(II)complex was an oxidative cleavage, while the mechanism by zinc(II)complex was a hydrolytic cleavage. The complexes exhibit powerful antibacterial activity.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► We synthesized two Robson-type macrocyclic complexes involved fluoro substituent. ► We studied the properties of the coordination polymers of them. ► The complexes exhibit powerful antibacterial activity.
