This compound has been obtained by two similar ways: The condensation of 6-iodo-1-methyl-1H-indole (I) with imidazole (II) by means of copper trifluoromethanesulfonate, 1,10-phenanthroline, Cs2CO3 and dibenzylideneacetone gives 6-(1-imidazolyl)-1-methyl-1H-indole (III), which is condensed with oxalyl chloride (IV) in dichloromethane to yield the adduct (V). Finally, this compound is cyclized with 2-(1-methyl-1H-indol-3-yl)acetimidic acid isopropyl ester (VI) by means of TEA in dichloromethane to afford the target pyrrolinedione. Alternatively, indole (I) and imidazole (II) are condensed by means of Pd2(dba)3, BINAP and tBu-ONa to give 6-(1-imidazolyl)-1-methyl-1H-indole (III), which is condensed with methoxalyl chloride (VII) in dichloromethane to yield the adduct (VIII). The reduction of (VIII) with NaH2PO2 affords the methyl acetate derivative (IX), which is treated with NH4OH to provide the acetamide derivative (X). Finally, this compound is cyclized with the methoxalyl derivative (XI) (obtained by condensation of 1-methyl-1H-indole (XII) with methoxalyl chloride (VII)) by means of tBu-ONa in THF to afford the target pyrrolinedione.