反应详情

To a solution of 2-(((Z)-(2-(((2R,3S)-2-((4-(aminomethyl)-2H-1,2,3-triazol-2-yl)methyl)-4-oxo-1-sulfoazetidin-3-yl)amino)-1-(2-aminothiazol-4-yl)-2-oxoethylidene)amino)oxy)-2-methylpropanoic acid (100 mg, 0.159 mmol) and ethylformamidate hydrochloride (17.4 mg, 0.159 mmol) in DMF (1 mL) was added DIPEA (41 mg, 0.32 mmol). After 2 h of stirring, more ethylformamidate hydrochloride (9.0 mg, 0.082 mmol) and DIPEA (20 mg, 0.16 mmol) was added. After an additional 4 h the solution was concentrated and washed with ether. The crude residue was purified by reverse phase prep HPLC (XSelect CSH, 30×100 mm, 5 μm, C18 column; ACN-water with 0.1% formic acid modifier, 60 mL/min), affording the title compound (15.5 mg, 18%) as mixture of amidine tautomers. LCMS: m/z=556.8 (M−1); 1H NMR (400 MHz, D2O): δ 7.73 (s, 0.4H), 7.65 (s, 0.6H), 7.57 (m, 1H), 6.83 (s, 1H), 5.37 (d, J=5.6 Hz, 1H), 4.80-4.61 (m, 3H assumed; obscured by solvent residual peak) 4.48 (s, 0.4H), 4.45 (s, 0.6H), 1.17 (s, 3H), 1.15 (s, 3H).

1. concentrationAfter an additional 4 h the solution was concentrated
2. washwashed with ether
3. customThe crude residue was purified by reverse phase prep HPLC (XSelect CSH, 30×100 mm, 5 μm, C18 column; ACN-water with 0.1% formic acid modifier, 60 mL/min)