Reacción #6754

Ecuación de reacción

citric acid monohydrate

water

3-(β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-1-isopropyl-5-methylpyrazole

ethyl chloroformate

→

3-(6-O-ethoxycarbonyl-β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-1-isopropyl-5-methylpyrazole

Rendimiento 72.4%

Disolventes

2,4,6-trimethylpyridine

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.DISTILLATIONthe resulting mixture was purified by ODS solid phase extraction (washing solvent: distilled water, eluent: methanol)
2. 2
   OtroFurther purification by column chromatography
3. 3
   Otroon silica gel (eluent: dichloromethane/methanol=1011) and recrystalization (recrystalization solvent: ethyl acetate/hexane=1/3)

Procedimiento

To a solution of 3-(β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-1-isopropyl-5-methylpyrazole (0.10 g) in 2,4,6-trimethylpyridine (1 mL) was added ethyl chloroformate (0.072 g), and the mixture was stirred at room temperature overnight. To the reaction mixture were added citric acid monohydrate (3.3 g) and water, and the resulting mixture was purified by ODS solid phase extraction (washing solvent: distilled water, eluent: methanol). Further purification by column chromatography on silica gel (eluent: dichloromethane/methanol=1011) and recrystalization (recrystalization solvent: ethyl acetate/hexane=1/3) afforded 3-(6-O-ethoxycarbonyl-β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-1-isopropyl-5-methylpyrazole (0.084 g).

Fuente