Sodium hydride → (R)-1-(5-acetoxyhexyl)-8-bromo-7-ethoxymethyl-3-methylxanthine

8-Bromo-7-ethoxymethyl-3-methylxanthine (prepared as described for CT12440) (3.03 g, 10 mmol) was added to a suspension of sodium hydride (264 mg, 11 mmol) in anhydrous dimethylsulfoxide (60 ml). After stirring for 30 minutes, (R) 5-acetoxy-1-chlorohexane (1.963 g, 11 mmol) was added and the mixture was heated at 70-80° C. for 12 hours. After cooling to room temperature, the reaction was quenched by the addition of water (150 ml) and extracted with 10% methanol-ethyl acetate (3x 25 ml). The combined extracts were washed with water (2x 50 ml), with saturated aqueous sodium chloride solution (50 ml), dried over magnesium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel eluting with 30% ethyl acetate-hexane to provide (R)-1-(5-acetoxyhexyl)-8-bromo-7-ethoxymethyl-3-methylxanthine (2.778).

1. temperatureAfter cooling to room temperature
2. customthe reaction was quenched by the addition of water (150 ml)
3. extractionextracted with 10% methanol-ethyl acetate (3x 25 ml)
4. washThe combined extracts were washed with water (2x 50 ml), with saturated aqueous sodium chloride solution (50 ml)
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by flash chromatography on silica gel eluting with 30% ethyl acetate-hexane

ORD-Eintrag

ord-18d85b3f1f194a6ca194dfc4e3025d29

Quelldatensatz

uspto-grants-2005_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06878715B1