Calix[4]arenequinazolinones. Synthesis and structure

The synthesis of calix[4]arenes bearing two quinazolin-4-ones group at the upper rim is decribed. 1H NMR spectra and quantum chemical calculations make it possible to suggest that calix[4]arenequinazolinones form three rotamers in solutions at room temperature, due to the restricted rotation of the quinazolinone fragments. The X-ray structure investigation indicates that quinazolin-4-onecalix[4]arene exists in the crystal state as the methanol 1:1 inclusion complex.