Two-step solution-phase synthesis of novel quinoxalinones utilizing a UDC (Ugi/de-Boc/cyclize) strategy

The novel solution-phase synthesis of an array of biologically relevant quinoxalinones in a simple two-step procedure is revealed. Transformations are carried out in excellent yield by condensation of mono-Boc protected ortho-phenylene di-amine, glyoxylic acids and supporting Ugi reagents. Subsequent acid treatment and evaporation affords quinoxalinones in good to excellent yields.