反应详情

The same operation as in Example (102a) was performed using threonine methyl ester hydrochloride (2.88 g, 17 mmol), 3-methoxy-4-nitrobenzoic acid (3 g, 15.2 mmol), WSC hydrochloride (3.83 g, 20 mmol), DMAP (0.18 g, 1.5 mmol), N,N-diisopropylethylamine (2.58 g, 20 mmol) and dichloromethane (40 mL). The resulting residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/hexane=1/2, 1/1, 2/1, 1/0) to obtain 4.49 g of the title compound as a light yellow amorphous solid (95%).

1. customThe resulting residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/hexane=1/2, 1/1, 2/1, 1/0)