Reaction Steps
To a solution of phenyl dichlorophosphate (0.1 ml, 0.625 mmol) in DMF (0.1 ml) at 0° C. under inert atmosphere, was added dropwise a solution of 4-[({[3-(4-methoxyphenyl)-5-phenyl-1H-pyrrol-2-yl]carbonyl}amino)methyl]benzoic acid (0.206 g, 0.5 mmol) in CH2Cl2 (2.5 ml), and the resulting mixture was stirred at room temperature for 10 minutes. 2-(Tritylsulfanyl)aniline (0.404 g, 1.0 mmol) and triethylamine (4.17 ml, 30 mmol) were added subsequently, and the mixture was stirred at room temperature for 16 h. Ethyl acetate (40 ml) was added, and the obtained solution was washed with HCl 0.1N (3×7 ml), water (7 ml), and NaOH 1N (3×7 ml), dried over Na2SO4 and evaporated under reduced pressure. This material was dissolved in CH2Cl2 (5 ml), and cooled to 0° C. Trifluoroacetic acid (0.49 ml, 6.4 mmol) and triethylsilane (0.09 ml, 0.55 mmol) were added subsequently, and the resulting mixture was stirred at room temperature for 2 h. NaHCO3 (7.7 ml, saturated aqueous solution) was added and the resulting mixture was stirred for 30 min. The organic layer was separated and the aqueous layer was extracted with CH2Cl2 (3×15 ml). The combined organic fractions were dried over Na2SO4 and evaporated under reduced pressure, to obtain 0.216 g (0.404 mmol) of 3-(4-methoxyphenyl)-5-phenyl-N-(4-{[(2-sulfanylphenyl)amino]carbonyl}benzyl)-1H-pyrrole-2-carboxamide: Yield 81%; m.p. 134-135° C.; IR 3407, 3384, 3233, 1681, 1638, 1525, 1493, 1249 cm−1; 1H-NMR (300 MHz, δ ppm, CDCl3) 10.22 (s, 1H), 8.93 (s, 1H), 8.48 (dd, J=8.3 Hz, J′=1.0 Hz, 1H), 7.63 (d, J=8.3 Hz, 4H), 7.43-7.35 (m, 6H), 7.34-7.20 (m, 4H), 6.97-6.90 (m, 3H), 6.49 (d, J=3.0 Hz, 1H), 6.24 (t, J=6.0 Hz, 1H), 4.51 (d, J=6.0 Hz, 2H), 3.81 (s, 3H); 13C-NMR (126 MHz, δ ppm, DMSO-d6) 165.4, 161.2, 158.0, 143.5, 135.9, 133.5, 133.0, 132.3, 131.6, 129.9, 128.7, 127.9, 127.8, 127.6, 127.4, 127.1, 126.9, 126.8, 124.6, 123.9, 122.6, 114.0, 113.4, 108.3, 55.0, 42.2.
