Synthesis, Structural Features, and Molecular Docking of Zinc Complexes with Derivatives of 3-Arylidene-1-Pyrrolines

A series of zinc complexes with 3-arylidene-1-pyrrolines and acetic or trifluoroacetic acid anions is obtained. Molecular and crystal structures are investigated and non-covalent interactions are analyzed for all synthesized compounds. The molecular structures of the complexes are shown to be similar. Minor differences are due to non-covalent interactions whose nature and amount is determined by the occurrence of active centers in the ligand compositions. It is revealed that for 3-arylidene-1-pyrroline complexes the main structure-forming interaction is π⋯π interactions of different topologies. The exceptions are only the crystals of compounds containing groups being donors of hydrogen bonds (e.g., hydroxyl groups), which results in the formation of hydrogen-bonded associates that in turn form the crystal packing mainly by π⋯π interactions. The molecular docking-modeling with the HER2 human receptor kinase domain indicates that the obtained complexes can bind with HER2 with an energy gain comparable with that for the previously studied copper trifluoroacetate complexes with 3-arylidene-1-pyrrolines. This fact suggests that they are effective in anticancer therapy.