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The condensation of methyl 2,3-diaminobenzoate (I) with isatin (II) in refluxing AcOH afforded a mixture of indoloquinoxaline-carboxylates (III) and (IV), which were separated by column chromatography. The desired 4-carboxylate isomer (III) was methylated at the indole N atom with CH3I in the presence of NaH to provide (V). The ester group of (V) was reduced to alcohol (VI) with LiAlH4 and then oxidized with activated MnO2 to yield aldehyde (VII). Subsequent condensation of (VII) with amine (VIII) in refluxing toluene in the presence of p-toluenesulfonic acid produced the corresponding imine (IX), which was finally reduced with NaBH4 in EtOH to the target amine, which was isolated as the hydrochloride salt.