Decarboxylation of methyl 3-aminothiophene-2-carboxylate (I) in 2 N NaOH leads to 3-aminothiophene (II). Meldrum's acid (III) is condensed with triethyl orthoformate to produce the ethoxymethylene derivative (IV). Subsequent reaction of enol ether (IV) with 3-aminothiophene (II) gives rise to enamine (V), which is further cyclized to thienopyridinone (VI) upon heating in dowtherm A at 260 C. This is then chlorinated by means of oxalyl chloride to furnish 4-chlorothieno[3,2-b]pyridine (VII). Metalation of (VII) with butyllithium in cold THF, followed by treatment with I2 affords the aryl iodide (VIII). Palladium-catalyzed coupling of (VIII) with the lithiated derivative of 1-methylimidazole (IX) yields (X). Finally, displacement of the chloride group of (X) with 5-amino-2-methylindole (XI) provides the title compound.

Decarboxylation of methyl 3-aminothiophene-2-carboxylate (I) in 2 N NaOH leads to 3-aminothiophene (II). Meldrum's acid (III) is condensed with triethyl orthoformate to produce the ethoxymethylene derivative (IV). Subsequent reaction of enol ether (IV) with 3-aminothiophene (II) gives rise to enamine (V), which is further cyclized to thienopyridinone (VI) upon heating in dowtherm A at 260 C. This is then chlorinated by means of oxalyl chloride to furnish 4-chlorothieno[3,2-b]pyridine (VII). Metalation of (VII) with butyllithium in cold THF, followed by treatment with I2 affords the aryl iodide (VIII). Palladium-catalyzed coupling of (VIII) with the lithiated derivative of 1-methylimidazole (IX) yields (X). Finally, displacement of the chloride group of (X) with 5-amino-2-methylindole (XI) provides the title compound.