Diisopropylethylamine → HCID 57920021, Verbindung

Beteiligte Stoffe

Reaktionsschritte

A suspension of (2S,4S)-2-amino-4-ethoxy-pentanoic acid [1-(2-hydroxy-2-methyl-propyl)-1H-pyrazol-3-yl]-amide hydrochloride salt (prepared as in Example 95, 124.5 mg, 0.335 mmol) in acetonitrile (7 mL) was treated with N,N-diisopropylethylamine (0.25 mL). At this time a solution of (E)-4-bromo-3-(3-ethoxy-2-fluoro-phenoxy)-but-2-enoic acid ethyl ester (prepared as in Example 114, 117 mg, 0.337 mmol) in acetonitrile (2 mL) was added and the resulting solution refluxed for 64 h. The mixture was concentrated in vacuo and the residue partitioned between ethyl acetate and water. The layers were separated and the organic layer was dried over anhydrous sodium sulfate. The mixture was filtered and concentrated in vacuo and the residue dissolved in tetrahydrofuran (2 mL) and transferred to an Emrys Optimizer microwave tube and microwaved at 160° C. for 1.5 h. The mixture was concentrated in vacuo and the residue was purified by ISCO flash chromatography (RediSep silica 12 g, 10% to 70% (10% methanol/dichloromethane)/hexanes,) which afforded (2S,4S)-4-ethoxy-2-[4-(3-ethoxy-2-fluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-pentanoic acid [1-(2-hydroxy-2-methyl-propyl)-1H-pyrazol-3-yl]-amide (87 mg, 50%): HR-ES-MS (m/z) calculated for C26H35FN4O6 [M+H]+ 519.2614, observed 519.2615. 1H NMR (300 MHz, DMSO-d6) δ ppm 0.95-1.19 (m, 12H), 1.36 (t, J=6.0 Hz, 3H), 1.75-2.02 (m, 2H), 3.15-3.30 (m, 1H), 3.33 (br. s., 1H), 3.40-3.55 (m, 1H), 3.89 (br. s., 2H), 4.06-4.21 (m, 2H), 4.29 (d, J=18.4 Hz, 1H), 4.49 (d, J=18.4 Hz, 1H), 4.67 (br. s., 1H), 4.85-4.99 (m, 2H), 6.44 (br. s., 1H), 6.91-7.06 (m, 1H), 7.05-7.29 (m, 2H), 7.53 (br. s., 1H), 10.69 (br. s., 1H).

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