In this abstract we present the use of a carbohydrazone based ligand and bis(pyridyl) compounds, containing pyridine groups linked to the two ends of a spacer, to build 1D coordination polymers. By the interaction of 1,5-bis(2-hydroxybenzaldehyde)carbohydrazone (H4L) with copper nitrate in the presence of 4,4'-bipyridine (bpy) and 1,2-bis(4-pyridyl)ethane (bpe) in dimethylformamide (DMF) the compounds {[Cu2(HL)(bpy)(H2O)(NO3)]·DMF}n (1) (Figure 1, right) and {[Cu2(HL)(bpe)(H2O)(NO3))]·DMF}n (2) were synthesized. In the obtained compounds, the ditopic ligand coordinates hexadentately in the trideprotonated form HL3– through the ONN and ONO donor atom sets, which are formed as a result of its tautomerization. The generated binuclear monocations [Cu2(HL)(bpy)(H2O)(NO3)]+ are linked via bpy bridges (in 1) (Figure 1, left) and bpe (in 2), forming 1D dimensional polymers. It should be mentioned, that copper ions from both compartments ONN and ONO are involved in polymerization. In compound 1, the Cu1 atom (coordinated by the ONN set) in the axial position has a monodentately coordinated nitrate anion, while to the Cu2 atom (coordinated by the ONO set) a water molecule is coordinated. In compound 2 the water molecule and the ion nitrate are interchanged. As a result, the coordination number of all copper ions is 5, and the coordination polyhedra are square pyramids. In compound 1, the Cu1–Cu2 distance within the binuclear unit is 4.812 Å, and those connected via bpy, that are Cu1-Cu1' and Cu2-Cu2', are 11.108 Å and 11.086 Å,. In compound 2, these values are 4.770 Å, 13.136 Å (Cu1-Cu1') and 13.357 Å(Cu2-Cu2'), respectively. An extended network of hydrogen bonds involving hydrazine nitrogen atoms, nitrate anions and DMF molecules join the components of the crystal in 1 and 2.Figure 1. Structure of the monocation [Cu2(HL)(bpy)(H2O)(NO3)]+ (left) and the polymeric chain (right) of compound 1 (coordinated nitrate ion is omitted for clarity)