Реакция #61098

Уравнение реакции

diphosgene

(2S,3S)-2-{(R)-2-amino-2-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-acetylamino}-3-phenyl-N-(4-propionyl-thiazol-2-yl)-butyramide

diisopropylethylamine

→

(2S,3S)-2-{2,5-dioxo-4-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-imidazolidin-1-yl}-3-phenyl-N-(4-propionyl-thiazol-2-yl)-butyramide

Выход 35.9%

Растворители

tetrahydrofuran

tetrahydrofuran

Условия реакции

Обработка

1. 1
   Другоеpartitioned between ethyl acetate and water
2. 2
   ДругоеThe organic layer was separated
3. 3
   Сушкаdried over sodium sulfate
4. 4
   Фильтрацияfiltered
5. 5
   Концентрированиеconcentrated in vacuo
6. 6
   ДругоеThe residue was purified by chromatography over silica gel
7. 7
   Промывкаeluted first with ethyl acetate
8. 8
   Промывкаgradient eluted with dichloromethane containing from 0 to 10% methanol
9. 9
   ДругоеPrecipitation of the isolated product from dichloromethane with an excess of hexanes

Методика

Crude (2S,3S)-2-{(R)-2-amino-2-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-acetylamino}-3-phenyl-N-(4-propionyl-thiazol-2-yl)-butyramide (≈0.16 mmol) was dissolved in tetrahydrofuran (10 mL) that contained diisopropylethylamine (142 μL, 105 mg, 0.81 mmol) and was transferred via cannula to a solution of diphosgene (14 μL, 23 mg, 0.12 mmol) in tetrahydrofuran (15 mL) at 0° C. The reaction mixture was stirred for 20 minutes and then partitioned between ethyl acetate and water. The organic layer was separated and dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by chromatography over silica gel eluted first with ethyl acetate and then gradient eluted with dichloromethane containing from 0 to 10% methanol. Precipitation of the isolated product from dichloromethane with an excess of hexanes gave (2S,3S)-2-{2,5-dioxo-4-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-imidazolidin-1-yl}-3-phenyl-N-(4-propionyl-thiazol-2-yl)-butyramide as a white solid (26 mg, 27%).

Источник