Reaction Steps
2-(R)-(3-Chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionic acid (prepared as in PCT WO 2004/052869 A1, Example 1, 500 mg, 1.52 mmol) was suspended in methylene chloride (7.6 mL) and a 2.0 M solution of oxalyl chloride in methylene chloride (760 μL, 1.52 mmol) was added and the reaction stirred at 25° C. for 10 min. The solution was chilled to 0° C. and 2,6-lutidine (354 μL, 3.04 mmol) was added. The reaction continued to stir at 0° C. for 15 min. [3-(3-Amino-pyrazol-1-ylmethyl)-phenyl]-carbamic acid tert-butyl ester (437 mg, 1.52 mmol) was dissolved in methylene chloride (7 mL) and added dropwise to the reaction. The ice bath was removed and the reaction continued to stir at 25° C. for 30 min. The reaction was diluted with ethyl acetate (300 mL), washed with water (2×50 mL), saturated aqueous brine solution (20 mL), dried over magnesium sulfate and concentrated in vacuo to a yellow foam. Purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 120 g; 5% ethyl acetate/methylene chloride to 15% ethyl acetate/methylene chloride) afforded (3-{3-[2-(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionylamino]-pyrazol-1-ylmethyl}-phenyl)-carbamic acid tert-butyl ester (539 mg 59%) as a pale pink powder: ESI-LRMS m/e calcd for C30H37ClN4O5S [M+] 600.22, found 601.50 [M+H+]; 1H NMR (400 MHz, CDCl3) δ ppm 1.03-1.23 (m, 2H, CH2), 1.45-1.93 (m, 8H, 4×CH2), 1.51 (s, 9H, 3×CH3), 2.15-2.30 (m, 1H, CH), 3.26 (s, 3H, SO2CH3), 3.54 (t, J=7.8 Hz, 1H, CH), 5.11 (s, 2H, NCH2), 6.49 (brs, 1H, NH), 6.71 (d, J=2.5 Hz, 1H, Ar), 6.82 (m, 1H, Ar), 7.19-7.25 (m, 2H, Ar), 7.26-7.29 (brs, 1H, Ar), 7.31 (d, J=2.5 Hz, 1H, Ar), 7.45 (dd, Jo=8.2, Jm=1.6 Hz, 1H, Ar), 7.59 (d, Jm=1.6 Hz, 1H, Ar), 8.08 (d, Jo=8.2 Hz. 1H, Ar), 8.17 (brs, 1H, NH).
