Methylamine → Methyl 4-(4-(dibutylcarbamoyl)-1-(2-(methylamino)-2-oxoethyl)-1H-imidazol-2-yl)-3-(1,2,3,4-tetrahydroisoquinoline-2-carbonyl)benzoate

Participants

Reaction Steps

To a solution of 2-(4-(dibutylcarbamoyl)-2-(4-(methoxycarbonyl)-2-(1,2,3,4-tetrahydroisoquinoline-2-carbonyl)phenyl)-1H-imidazol-1-yl)acetic acid (180 mg, 0.31 mmol) in dry DMF (5 mL) was added HATU (595 mg, 1.56 mmol), methylamine (Aldrich, 78 μL, 1.56 mmol, 2.0 M in THF) and diisopropylethyl amine (544 μL, 3.13 mmol) at 0° C. The reaction mixture was allowed to warm to room temperature over 30 min and stirring was continued for 16 h. The reaction mixture was diluted with water, and extracted with EtOAc (3×). The combined organic layers were dried over Na2SO4 and concentrated in vacuo to give crude product. The crude material was purified by flash chromatography (gradient from 20 to 50% EtOAc/hexanes) to provide (85 mg, 46%). 1H NMR (CDCl3, 1:1 mixture of amide rotamers) δ 8.22-8.19 (m, 1H), 8.10 (dd, J=6.0, 1.6 Hz, 1H), 7.58 (s, 0.5H), 7.56-7.52 (m, 1H), 7.50 (s, 0.5H), 7.36-7.10 (m, 3.5H), 6.94 (d, J=7.6 Hz, 0.5H), 4.76 (br s, 1H), 4.65 (br s, 3H), 3.98 (s, 3H), 3.97-3.95 (m, 1.5H), 3.73 (t, J=5.6 Hz, 1.5H), 3.60-3.30 (m, 3H), 3.00-2.85 (m, 2H), 2.65 (s, 1.5H), 2.64 (s, 1.5H), 1.47-1.24 (m, 6H), 0.96-0.84 (m, 5H), 0.80 (t, J=7.4 Hz, 1.5H), 0.60 (t, J=7.4 Hz, 1.5H); MS(ESI+) m/z 588.4 (M+H)+.

Provenance & Evidence