Mono- and di-acylated imidazolidine-2-thione derivatives: synthesis, cytotoxicity evaluation and computational studies

Imidazolidine-2-thione substructure represents a pharmaceutically attractive scaffold, being included in different antimicro- bial, anticancer and pesticide agents. To further evaluate the pharmaceutical potential of this chemical moiety, imidazolidine- 2-thione was reacted with atypical Vilsmeier adducts, obtained by the condensation between dimethylacetamide and various acyl chlorides endowed with different electronic and steric properties. The formation of mono-acylated or di-acylated thio- urea derivatives emerged to be affected by the nature of the considered acyl chloride reagent. Computational semi-empirical simulations were carried out to rationalize the relevant factor influencing the outcome of the reaction. As acylthioureas are pharmacologically relevant compounds, the chemical versatility of mono-acylated derivatives were evaluated by reacting benzoyl imidazolidin-2-thione with acyl chlorides. A small library of asymmetric di-acylthioureas was prepared and the obtained derivatives did not show any cytotoxicity on SKOV-3 and MCF-7 cancer cell lines. Additionally, in silico studies predicted good pharmacokinetics properties and promising drug-like characteristics for mono- and di-acylated thioureas. These considerations further support the value of the prepared compounds as interesting non-cytotoxic chemical scaffold useful in the medicinal chemistry field.