Diazotization of substituted aniline (I) followed by reaction with ethyl 2-chloro-3-oxobutanoate (II) in MeOH yields hydrazono chloroacetate derivative (III), which is converted into oxamidrazonate (IV) by means of NH3 (gas). Treatment of derivative (IV) with ethyloxalyl chloride (V) affords ethoxalyl derivative (VI), which is then heated until cyclization occurs, providing derivative (VII). Reduction of triazole dicarboxylate (VII) with iron in HOAc gives tricyclic compound (VIII), which is nitrated by means of HNO3 to afford nitro derivative (IX). Reduction of the nitro group of (IX) by means of iron in HOAc provides the corresponding 8-amino derivative (X), which is treated with diformylhydrazine and trimethylsilyl chloride (TMSCl) in pyridine to furnish ethyl carboxylate (XI). Finally, saponification of (XI) with NaOH in EtOH gives the desired compound.