Complexes [Cu(CH3COO)(dppz)2]CH3COO (1) and [Zn(dppz)2](BF4)2 (2) with the intercalator dipyridophenazine (dppz) were prepared to obtain metallointercalators with increased geometrical flexibility compared to octahedral ones. Biophysical results (thermal denaturation, circular dichroism, rheometry, atomic force microscopy) indicate a strong interaction with DNA by intercalation and the existence of a positive cooperative effect with groove binding being preferred at low concentration of complexes. Induced circular dichroism (ICD) studies with DNA show that compounds 1 and 2 have a preferred orientation when binding to DNA. Since the compounds lack functional groups to permit hydrogen bonds, a combined intercalation/covalent binding mode is plausible. Further studies by QTof-ESI-MS and tandem experiments with GC oligonucleotides strongly support this dual-binding mode, since binding requires loss of one dppz unit with the copper center remaining attached to DNA even after another dppz loss. DNA saturation ...

Nonclassic metallointercalators with dipyridophenazine: DNA interaction studies and leishmanicidal activity.

In the title complex, [Cu(CH3CO2)(C12H8N2)2](CH3CO2)·7H2O, the central CuII ion is five coordinate, being bound to four N atoms from two 1,10-phenanthroline ligands and one O atom from an acetate anion in a strongly distorted square-pyramidal configuration Hydrogen-bonded water mol­ecules and an uncoordinated acetate anion form a two-dimensional polymeric structure parallel to (010) The cations are linked to this layer via O—H⋯O hydrogen bonds between one of the water mol­ecules and the coordinated acetate anion

https://journals.iucr.org/e/issues/2011/04/00/gk2351/gk2351.pdf

(Acetato-κO)bis­(1,10-phenanthroline-κ2N,N′)copper(II) acetate hepta­hydrate

The dinuclear title compound, [Co2(C10H8N4O4)2(H2O)4]·6H2O, lies about an inversion centre. Each CoII atom is six-coordinated by two water mol­ecules, two carboxyl­ate O atoms and two N atoms of two symmetry-related 2,2′-bi-1H-imidazole-1,1′-diacetate (L2−) ligands in a slightly distorted octa­hedral geometry. Mol­ecules are linked into a three-dimensional framework via O—H⋯O and C—H⋯O hydrogen bonds.

https://journals.iucr.org/e/issues/2009/05/00/sj2607/sj2607.pdf

Bis(μ-2,2'-bi-1H-imidazole-1,1'-di-acet-ato)bis-[diaqua-cobalt(II)] hexa-hydrate.

In the title compound, C20H20N4O4, the complete molecule is generated by a crystallographic centre of symmetry The conformation is stabilized by two intramolecular C—H⋯N links

https://journals.iucr.org/e/issues/2009/07/00/fb2148/fb2148.pdf

Di-tert-butyl 3,3'-(2,2'-bi-1H-imidazole-1,1'-di-yl)dipropanoate.

In the title compound, C10H10N4O4, the two imidazole rings adopt a trans conformation and are inclined to one another at a dihedral angle of 55.64 (4)°. In the crystal structure, mol­ecules are linked by inter­molecular O—H⋯N hydrogen bonds into chains running parallel to [010] and layers are formed from these by inter­molecular C—H⋯O hydrogen bonds. Additional C—H⋯O hydrogen bonds produce a three-dimensional network.

https://journals.iucr.org/e/issues/2009/04/00/sj2599/sj2599.pdf

2,2'-(2,2'-Biimidazole-1,1'-di-yl)diethanoic acid.

In the title compound, [Cu(C8H7O2)(C12H8N2)2](C8H7O2)·6H2O, the Cu atom is in a distorted square-pyramidal coordination environment The six crystallographically independent uncoordinated water mol­ecules are inter­connected by hydrogen bonds, completing dodeca­water (H2O)12 clusters which are hydrogen bonded to the carboxyl­ate groups of phenyl­acetate anions, building up one-dimensional anionic chains propagating along [100] Between the cationic and anionic chains are hydrogen bonds from water mol­ecules to the carboxyl­ate O atoms belonging to the phenyl­acetato ligands

https://journals.iucr.org/e/issues/2008/11/00/pk2118/pk2118.pdf

Bis(1,10-phenanthroline-κ2N,N′)(phenylacetato-κO)copper(II) phenylacetate hexahydrate

In the title compound, [Cu(C4H2BrO4)2(C6H6N4)2], the central CuII atom lies on an inversion center and is six-coordinated in an octahedral geometry by four N atoms from two chelating biimidazole mol­ecules in the equatorial plane and two O atoms from two 2-bromo­fumarate ligands in the axial positions. O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds lead to a three-dimensional network.

/pdf/bis-2-2-biimidazole-kn-n-bis-2-bromo-fumarato-ko-copper-ii-10ig7ube26.pdf

Bis(2,2'-biimidazole-κN,N')bis-(2-bromo-fumarato-κO)copper(II).

The list of authors in the paper by Zhi, Long, Chen & Ren [Acta Cryst. (2009), E65, o2008] is corrected and the acknowledgements are updated.

/pdf/erratum-3-3-2-2-bi-1h-imidazole-1-1-di-yl-dipropanamide-2i7ng5skn3.pdf

Ying-Tao Ren

Papers

2,2'-(2,2'-Biimidazole-1,1'-di-yl)diethanoic acid.

Bis(1,10-phenanthroline-κ2N,N′)(phenylacetato-κO)copper(II) phenylacetate hexahydrate

Bis(2,2'-biimidazole-κN,N')bis-(2-bromo-fumarato-κO)copper(II).

Erratum: 3,3'-(2,2'-Bi-1H-imidazole-1,1'-di-yl)dipropanamide. Corrigendum.