Treatment of o-nitroaniline (I) with 6-bromo-1,2,3,4-tetrahydro-1,1,4,4-tetramethylnaphtalene (II), K2CO3 and CuI in xylene yields diphenylamine derivative (III), which is then N-methylated by means of NaH and MeI in DMF to provide (IV). Reduction of the nitro group of (IV) by hydrogenation over Pd/C in ethanol or by treatment with Fe and HCl in H2O/EtOH affords the corresponding amine derivative (V), which is then condensed with terephthalic acid monomethyl ester chloride (VI) in benzene/pyridine to furnish compound (VII). Cyclization of (VII) by means of polyphosphoric acid (PPA) in CH2Cl2 gives diazepin derivative (VIII), which is finally converted in the target product by first nitration with KNO3 in H2SO4 followed by hydrolysis with NaOH in EtOH.

Treatment of o-nitroaniline (I) with 6-bromo-1,2,3,4-tetrahydro-1,1,4,4-tetramethylnaphtalene (II), K2CO3 and CuI in xylene yields diphenylamine derivative (III), which is then N-methylated by means of NaH and MeI in DMF to provide (IV). Reduction of the nitro group of (IV) by hydrogenation over Pd/C in ethanol or by treatment with Fe and HCl in H2O/EtOH affords the corresponding amine derivative (V), which is then condensed with terephthalic acid monomethyl ester chloride (VI) in benzene/pyridine to furnish compound (VII). Cyclization of (VII) by means of polyphosphoric acid (PPA) in CH2Cl2 gives diazepin derivative (VIII), which is finally converted in the target product by first nitration with KNO3 in H2SO4 followed by hydrolysis with NaOH in EtOH.