Rapid assembly of 2-aminoimidazolones on solid support

A straightforward solid-phase synthesis of 2-aminoimidazolone derivatives is described. The synthesis starts with immobilization of thioureas onto solid support, followed by HBTU/DIEA assisted coupling of Boc-protected amino acids. Upon removal of the Boc group, intramolecular cyclization and simultaneous cleavage are promoted by polyamine resin to give the 2-aminoimidazolone derivatives in good yields and excellent purity.