A small screw cap test tube was charged with 5-Acetyl-thiophene-2-carboxylic acid [4-(3-hydroxymethylene-2-oxo-2,3-dihydro-1H-indole-6-carbonyl)-phenyl]-amide (prepared below, 50 mg, 0.116 mmol) and THF (2 mL). To the resulting solution was added N-(4-aminophenyl)morpholine (20.0 mg, 0.1122 mmol), and the mixture was stirred for 24 h at 65° C. Subsequently, the reaction mixture was cooled to room temperature and concentrated in vacuo. The solid residue was recrystallized with ˜2 mL of i-prOH affording the title compound in 64% yield (0.044 g, 0.0742 mmol).
