反应详情

A solution of (3R)-6-cyclohexyl-3-[3-(1H-imidazol-2-ylmethyl)-1,2,4-oxadiazol-5-yl]hexanoic acid (Preparation 103) (200 mg, 0.43 mmol) in anhydrous tetrahydrofuran (5 ml) was treated with 1,1′-carbonyidiimidazole (77 mg, 0.48 mmol) and stirred under a nitrogen atmosphere for 30 minutes. O-(Trimethylsilyl)hydroxylamine (160 μl, 1.30 mmol) was added and the mixture was stirred for 18 hours. The mixture was then treated with methanol (4 ml) and stirred at room temperature for 1 hour. The solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel eluting with 90:10:1 (dichloromethane:methanol:ammonia) to afford a colourless oil which began to crystallise once a little methanol and dichloromethane were added. The solid was triturated with dichloromethane and dried under reduced pressure to afford the title compound as a solid (49 mg).

1. stirringthe mixture was stirred for 18 hours
2. stirringstirred at room temperature for 1 hour
3. customThe solvent was removed under reduced pressure
4. customThe residue was purified by column chromatography on silica gel eluting with 90:10:1 (dichloromethane:methanol:ammonia)
5. customto afford a colourless oil which
6. customto crystallise once a little methanol and dichloromethane
7. additionwere added
8. customThe solid was triturated with dichloromethane
9. customdried under reduced pressure