反应详情

A solution of (3-amino-propyl)-cyclopropylmethyl-carbamic acid tert-butyl ester (5 g, 0.022 mol), (3-bromo-2-oxo-2H-pyrazin-1-yl)-acetic acid ethyl ester (5.2 g, 0.020 mol, preparation described in example 17, step J) and triethylamine (3.3 ml, 0.024 mol) in ethanol (16 ml) was heated to 80° C. in a sealed tube overnight. Concentration and flash chromatography (silica gel, chloroform-diethyl ether, 90: 10) gave {3-[3-(tert-butoxycarbonyl-cyclopropylmethyl-amino)-propylamino]-2-oxo-2H-pyrazin-1-yl}-acetic acid ethyl ester; 1H NMR (CDCl3, 400 MHz) δ 6.85 (d, 1H, J=4.7 Hz), 6.36 (d, 1H, J=4.7 Hz), 4.56 (s, 2H), 4.25 (q, 2H, J=7.1 Hz), 3.42 (m, 2H), 3.36 (m, 2H), 3.10 (m, 2H), 1.87 (m, 2H), 1.46 (s, 9H), 1.30 (t, 3H, J=7.1 Hz), 0.96 (m, 1H), 0.48 (m, 2H), 0.20 (m, 2H).

1. concentrationConcentration and flash chromatography (silica gel, chloroform-diethyl ether, 90: 10)