Ethanolamine → [(S)-2-[7-(2-Hydroxyethylcarbamoyl)-furo[2,3-g]indazol-1-yl]-1-methylethyl]-carbamic acid benzyl ester

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Reaction Steps

A stirred solution of the product from Step A, Example 2 (0.44 g, 0.91 mmol) in ethanolamine was heated at 80° C. for 8 h. A saturated aqueous solution of ammonium chloride (20 mL) was added and the mixture was extracted with ethyl acetate (3×50 mL). The combined extracts were washed with brine, dried and evaporated to a residue, which was purified by chromatography (silica, 60% ethyl acetate in hexane) to give an oil (0.23 g, 57%): MS (ES) m/z 437 (M+); 1H NMR (CDCl3) δ 8.00 (s, 1H), 7.69 (d, 1H, J=8.0 Hz), 7.22-7.30 (m, 7H), 5.30 (brs, 1H), 5.03 (m, 2H), 4.63 (m, 1H), 4.40 (m, 1H), 4.15 (m, 1H), 3.85 (m, 2H), 3.65 (m, 2H), 1.26 (d, 3H, J=8.0 Hz).

Provenance & Evidence