反应详情

To a solution of 4-hydroxy-2-{1-[2-(4-methoxyphenyl)-1-(methylcarbamoyl)-ethylcarbamoyl]cyclohexylmethyl}butyric acid tert-butyl ester (490 mg, 1.0 mmol) in dry tetrahydrofuran (20 mL) was added 1,3-dioxo-1,3-dihydrobenzo[f]isoindole (394 mg, 2.0 mmol), triphenylphosphine (524 mg, 2.0 mmol) and diethylazodicarboxylate (0.31 mL, 2.0 mmol). The resulting mixture was stirred for 3 days. The solvent was evaporated under vacuum and the residue was chromatographed on silica gel eluting with 40% ethyl acetate in hexane. Fractions containing the two diastereomeric products were combined and evaporated to leave a white solid which was recrystallized from ethyl acetate to afford 4-(1,3-dioxo-1,3-dihydrobenzo [f]isoindol-2-yl)-2-{1-[2-(4-methoxyphenyl)-1-(methylcarbamoyl)-ethylcarbamoyl]cyclohexylmethyl}butyric acid tert-butyl ester (diastereomer A) as a white solid, 105 mg (16%). The mother liquor from the recrystallization was concentrated under vacuum to afford an oil highly enriched in diastereomer B, 140 mg (21%).

1. customThe solvent was evaporated under vacuum
2. customthe residue was chromatographed on silica gel eluting with 40% ethyl acetate in hexane
3. additionFractions containing the two diastereomeric products
4. customevaporated
5. customto leave a white solid which
6. customwas recrystallized from ethyl acetate