反应详情

A solution of a mixture of ethyl 4-{4-[(hydroxyamino)(imino)methyl]-2H-indazol-2-yl}butanoate & ethyl 4-{4-[(hydroxyamino)(imino)methyl]-1H-indazol-1-yl}butanoat (D56) (4 g, 13.78 mmol), 3-chloro-4-[(1-methylethyl)oxy]benzoic acid (D3) (2.96 g, 13.78 mmol), EDC (2.91 g, 15.16 mmol) and HOBT (2.321 g, 15.16 mmol) in DMF (40 ml) was stirred at RT for 3 hrs to form intermediate then heated at 120° C. for 2 hrs to cyclise. The solution was cooled, diluted with EtOAc, washed with water 3× dried (magnesium sulphate) and evaporated. Purified by flash chromatography eluting with EtOAc/iso-hexane 1:3. The combined fractions were evaporated to give the title compound (1.5 g) as a white solid. MS (ES): C24H2535ClN4O4 requires 468; found (MH+) 469. δH (CDCl3, 400 MHz): 1.24 (3H, t), 1.46 (6H, d), 2.31 (4H, m), 4.12 (2H, q), 4.55 (2H, t), 4.73 (1H, m), 7.08 (1H, d), 7.52 (1H, dd), 7.62 (1H, d), 8.06 (1H, dd), 8.10 (1H, dd), 8.29 (1H, d), 8.70 (1H, d).

1. customto form intermediate
2. temperaturethen heated at 120° C. for 2 hrs
3. temperatureThe solution was cooled
4. washwashed with water 3×
5. dry with materialdried (magnesium sulphate)
6. customevaporated
7. customPurified by flash chromatography
8. washeluting with EtOAc/iso-hexane 1:3
9. customThe combined fractions were evaporated