反应详情

Weinreb amide formation. 4-carboxy isoxazole (obtained from Steps 1-4 above) was dissolved in THF and activated with EDC:HOBt:DIEA (1.5:1.5:1.5) and allowed to stand at rt for 5min. N-methoxymethylamine (1.5 equiv.) was then added. The reaction mixture was allowed to stand at rt overnight, after which it was diluted with EtOAc and washed with 10% citric acid, 10% NaHCO3, and brine. The solvent was removed, and the residue was purified by flash chromatography (EtOAc/petrol) and lyophilized in 90% MeCN/H2O to give the desired product as a white powder.

1. waitto stand at rt overnight
2. washwashed with 10% citric acid, 10% NaHCO3, and brine
3. customThe solvent was removed
4. customthe residue was purified by flash chromatography (EtOAc/petrol)