Synthesis, characterization, crystal structure and cytotoxicity of 2,4-bis(selenomethyl)quinazoline

Abstract

Organoselenium compounds have already been reported to be good anticarcinogenic candidates. A new selenoquinazoline derivative, 2,4-bis(selenomethyl)quinazoline (compound 1), has been synthesized, spectroscopically characterized and its crystal structure has been studied. An intermolecular coupling between C₂ and ${\text{H}}_{5}^{\prime }$ in the Heteronuclear Multiple Bond Correlation (HMBC) experiment has been observed. Assuming that the head-to-tail overlap of parallel molecules (as identified by X-ray diffraction) remains in solution to give bimolecular entities, the π–π interaction enables heteronuclear coupling between the former atoms with a three-bond distance [C₂···(π–π)···${\text{C}}_{5}^{\prime }$–${\text{H}}_{5}^{\prime }$]. The crystal structure of compound 1 has been solved by X-ray diffraction. It crystallizes in triclinic system, space group P−1. Unit cell parameters are a = 7.4969(7) Å, b = 8.7008(8) Å, c = 10.1666(9) Å, α = 110.215(2)°, β = 90.354(2)°, γ = 115.017(1)°. Linear chains in crystals of compound 1 are generated by C–H···Se and Se···Se bonds between molecules. Furthermore, head-to-tail overlap of parallel molecules, in which π–π interactions can occur, is observed. Compound 1 exhibited a cytotoxic effect in all of the evaluated tumoral cell lines and showed a higher cytotoxic effect in colon and breast cancer cell lines than etoposide, which was used as a reference compound.