反应详情

Dissolve 2-Methyl-5-{2-nitro-4-[2-(3,4,5-trimethoxy-phenyl)-acetylamino]-phenyl}-furan-3-carboxylic acid methyl ester (59) (50 mg, 0.10 mmol) in THF (1.0 mL) and MeOH (0.5 mL) at rt and add 1M aqu LiOH (525 μL, 0.52 mmol). Stir the reaction mixture for 17 h at rt. Add dropwise 1M aqu. HCl (5804, 0.58 mmol) and extract the mixture with EtOAc (3 times), wash the combined organic layer with brine and dry it with Na2SO4. Purify the obtained crude product by preparative TLC (silica gel, EtOAc/MeOH 9+1) to obtain 2-Methyl-5-{2-nitro-4-[2-(3,4,5-trimethoxy-phenyl)-acetylamino]-phenyl}-furan-3-carboxylic acid (60) (35 mg, 71%) as a brown sticky solid. 1H NMR (400 MHz, CDCl3): 2.61 (s, 3H); 3.70 (s, 2H); 3.86 (s, 3H); 3.87 (s, 6H); 6.51 (s, 2H); 6.85 (s, 1H); 7.29 (br.s, 1H); 7.58 (d, 1H, J=8.6 Hz); 7.62 (dd, 1H, J1=9.0 Hz, J2=2.2 Hz); 7.98 (d, 1H, J=2.0 Hz).

1. additionAdd dropwise 1M aqu
2. washwash the combined organic layer with brine
3. dry with materialdry it with Na2SO4
4. customPurify the
5. customobtained crude product by preparative TLC (silica gel, EtOAc/MeOH 9+1)