反应详情

4-(4-Bromo-2-fluorophenylamino)-5-fluoro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid hydroxyamide was prepared from 4-(4-bromo-2-fluorophenylamino)-5-fluoro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid tert-butoxyamide by TFA mediated deprotection. 4-(4-Bromo-2-fluorophenylamino)-5-fluoro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid tert-butoxyamide (35 mg, 0.081 mmol) was treated with TFA (0.63 mL). After 4 days stirring, the reaction mixture was concentrated under reduced pressure. Purification by flash column chromatography (10% MeOH in methylene chloride) followed by saturated NaHCO3 solution wash of an ethyl acetate solution of the product gave clean desired product (10 mg, 33%); MS APCI (+) m/z 356, 358 (M-OH, Br pattern) detected; 1H NMR (400 MHz, CD3OD) δ 7.84 (s, 1H), 7.35 (dd, 1H), 7.28 (d, 1H), 7.01 (td, 1H), 3.57 (s, 3H).

1. concentrationthe reaction mixture was concentrated under reduced pressure
2. customPurification by flash column chromatography (10% MeOH in methylene chloride)
3. washwash of an ethyl acetate solution of the product