Polynuclear metal complexes with aromatic nitrogen heterocycles are subject of growing interest due to their potentially useful physical properties such as magnetism and luminescence. Moreover, the use of the heterocyclic ligands has led to the rational design of supramolecular systems based on stacking interactions. The 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) is the versatile polyfunctional sixdentate N-donor ligand suitable for the formation of mono- and polynuclear complexes as well as coordination polymers. In the course of our work on developing multinuclear heterometallic complexes [1] we have try to obtain Cu(II)/Ln complexes based on tppz ligand, which on the best our knowledge have not been still reported. From the reaction of Dy(NO3)3·6(H2O), copper(II) nitrate trihydrate, tppz, and acetylacetonate (Hacac) in a mixture of MeCN/MeOH a new complex [Cu2(tppz)(H2O)4(NO3)][Cu2(tppz)(H2O)5](NO3)7·(MeOH)·4(H2O) has been isolated. The compound crystallizes in the monoclinic space group P21/c: a = 17.4577(4), b = 15.3812(4), c = 25.6154(9) Å, β = 99.342(3)°, V = 6787.0(4) Å3. The asymmetric part of the unit cell comprises two different binuclear cationic species, [Cu2(tppz)(H2O)4(NO3)]3+ (A) and [Cu2(tppz)(H2O)5]4+ (B) as shown in Figure, seven nitrate ions, methanol and four water molecules. In each dinuclear species, the bis-tridentate tppz ligand bridges two crystallographically independent Cu(II) atoms, in a N3 chelating mode with the Cu1···Cu2 separation being 6.529 and 6.511 Å in A and B, respectively.       Complex A Complex B One of the copper atoms in both binuclear species has similar square-bipyramidal 4+1+1 coordination surrounding which is constituted from three nitrogen atoms of tppz ligand (Cu1-N, 1.963-2.027 Å) and water molecule (Cu1-O1w, 1.971-1.982 Å) in the basal plane, and axial positions are occupy by two water molecules (Cu1-O2w, 2.262 (A); 2.229 (B) and Cu1-O3w, 2.512 (A); 2.613 (B) Å). The second copper atom possess a distorted square-pyramidal environment completed by a N3O2 donor set from three N atoms of tppz (Cu2-N, 1.957-2.027 Å), an O atom of NO3 anion (Cu2-O1, 2.004 Å) and H2O (Cu2-O4w, 2.127 Å) on the axial position in A, and two water molecules in B (Cu2-O4w, 2.102 and Cu2-O5w, 2.021 Å). Thus, the used synthetic route results in the formation of two differently charged homometallic cationic Cu(II) complexes, but does not provide the formation of a heterometallic Cu-Dy complex.