Reaction Steps
A solution of 5-(3-furyl)-3-(4-hydroxyphenyl)-1H-pyrrole-2-carboxylic acid (1.45 g, 5.5 mmol) and methyl 4-(aminomethyl)benzoate hydrochloride (1.10 g, 5.5 mmol) in DMF (27.5 ml) was cooled to 0° C. Triethylamine (4.22 ml, 30.25 mol), 1-hydroxybenzotriazole (0.81 g, 6.0 mmol), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (1.17 g, 6.0 mmol) and N-methylmorpholine (0.61 ml, 5.5 mmol) were added subsequently, and the mixture was stirred for 2 h at 0° C., and for an additional 96 h at room temperature. Ethyl acetate (400 ml) was added, and the obtained solution was washed with water (75 ml), Na2S2O3 1N (75 ml, aqueous solution), water (75 ml), NaHCO3 (75 ml, saturated aqueous solution), and NaCl (75 ml, saturated aqueous solution), dried over Na2SO4 and evaporated under reduced pressure, to obtain 1.43 g (3.47 mmol) of methyl 4-[({[5-(3-furyl)-3-(4-hydroxyphenyl)-1H-pyrrol-2-yl]carbonyl}amino)methyl]benzoate: Yield 63%; m.p. 223-224° C.; IR 3390, 3321, 1700, 1616, 1532, 1272 cm−1; 1H-NMR (500 MHz, δ ppm, DMSO-d6) 11.51 (s, 1H), 9.35 (s, 1H), 8.13 (s, 1H), 7.91 (d, J=8.2 Hz, 2H), 7.67 (tb, 1H), 7.37 (d, J=8.3 Hz, 3H), 7.26 (d, J=8.5 Hz, 2H), 6.93 (d, J=0.9 Hz, 1H), 6.73 (d, J=8.5 Hz, 2H), 6.38 (d, J=2.6 Hz, 1H), 4.45 (d, J=5.8 Hz, 2H), 3.85 (s, 3H); 13C-NMR (126 MHz, δ ppm, DMSO-d6) 166.0, 161.2, 156.3, 145.0, 143.6, 138.5, 129.9, 129.1, 128.1, 127.5, 127.4, 126.0, 125.9, 121.3, 118.2, 115.1, 108.7, 108.3, 51.9, 42.1.
