Reaktion #72129

Reaktionsgleichung

3-Pentanone

sodium triacetoxyborohydride

ethyl 2-[(3S,4R)-3-amino-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}piperidin-1-yl]-1,3-benzothiazole-7-carboxylate

Ethyl 2-[(3S,4R)-3-amino-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}piperidin-1-yl]-1,3-benzothiazole-7-carboxylate

sodium bicarbonate

→

title compound

Ausbeute 68.0%

Ethyl 2-{(3S,4R)-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-[(1-ethylpropyl)amino]piperidin-1-yl}-1,3-benzothiazole-7-carboxylate

Ausbeute 68.0%

Lösungsmittel

methanol

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooling
2. 2
   Extraktionfollowed by extraction with ethyl acetate
3. 3
   WaschenThe organic layer was washed with brine
4. 4
   Trocknendried over anhydrous sodium sulfate
5. 5
   SonstigeThe insoluble matter was separated by filtration
6. 6
   Einengenthe filtrate was concentrated under reduced pressure
7. 7
   SonstigeThe resulting residue was purified by silica gel column chromatography (eluate: hexane:ethyl acetate=1:1 v/v)

Vorschrift

3-Pentanone (68.9 μL, 0.65 mmol) and sodium triacetoxyborohydride (165 mg, 0.78 mmol) were added four times every two hours to a mixed solution of ethyl 2-[(3S,4R)-3-amino-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}piperidin-1-yl]-1,3-benzothiazole-7-carboxylate obtained in Example (202e) (62.0 mg, 0.13 mmol) in methanol (1 mL) and tetrahydrofuran (1 mL) under ice-cooling, and the mixture was stirred at room temperature for 15 hours. Saturated aqueous sodium bicarbonate solution was added to the reaction solution, followed by extraction with ethyl acetate. The organic layer was washed with brine and dried over anhydrous sodium sulfate. The insoluble matter was separated by filtration, and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluate: hexane:ethyl acetate=1:1 v/v) to obtain 48 mg of the title compound (68%) as a colorless solid.

Quelle