Protonation and Zn(II) complexation with versatile valine and glycylglycine N-pyrimidines derivatives: crystal structures of layered {[Zn(HL1)2] · 2H2O}n and [Zn(HL2)2(H2O)4]

Amino-acids N-pyrimidine derivatives are bifunctional compounds showing a bipolar nature, as reveal the potentiometric and UV-Vis studies. These bifunctional and bipolar natures make them versatile ligands, either in solution or in solid state. The reaction of N-2-(4-amino-1,6-dihydro-1-methyl-5-nitroso-6-oxopyrimidinyl)-valine (H2L1) and -glycylglycine (H2L2) with Zn(II) in the same reaction conditions yield a layered {[Zn(HL1)2] · 2H2O}n and [Zn(HL2)2(H2O)4] complexes containing three different coordination modes (1η,μ-2η and μ-3η).