合成路线1

Condensation of 4,5-dichloro-1,2-phenylenediamine (I) with 1-phenyl-1,2-propanedione (II) in boiling AcOH provided quinoxaline (III). Subsequent reaction of (III) with ethyl bromopyruvate (IV) led to the pyrroloquinoxaline (V). After reduction of the ester group of (V) to alcohol (VI) with LiAlH4, further oxidation with MnO2 produced aldehyde (VII). This was condensed with boiling 3-(dimethylamino)propylamine (VIII), and the resulting imine (IX) was finally reduced to the target amine with NaBH4 in MeOH. The title compound was finally converted to the dioxalate salt upon treatment with oxalic acid in isopropanol.