General procedure: 5-((Z)-(5-fluoro-2-oxoindolidine-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3-carboxylic acid (100 g) was dissolved in dimethylformamide (500 ml), and benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (221 g), N-(2-aminoethyl)pyrrole (45.6 g) and triethylamine (93 ml). The reaction mixture was stirred at room temperature for 2 hours. After completion of the reaction, the solid product was collected by vacuum filtration and washed with ethanol. The resulting solid was slurried in ethanol (500 ml) by stirring at 64 °C for 1 h and subsequently cooled to room temperature. The solid was again collected by vacuum filtration, washed with ethanol and dried under vacuum to afford (Z)-5-((5-fluoro-2-oxoindol-3-ylidene)methyl)-2,4-dimethyl-N-(2-(pyrrolidin-1-yl)ethyl)-1H-pyrrole-3-carboxamide (101.5 g, 77% yield). The product was characterized by 1H-NMR (dimethylsulfoxide-d6): δ 1.60 (m, 4H, 2xCH2), 2.40,2.44 (2xs, 6H, 2xCH3), 2.50 (m, 4H, 2xCH2), 2.57,3.35 (2xm, 4H, 2xCH2), 7.53,7.70,7.73,7.76 (4 xm. 4H, aromatic and vinyl), 10.88 (s, 1H, CONH), 13.67 (s, 1H, pyrrole NH). Mass spectral analysis showed m/z 396 [M + 1].
