4-Toluenesulfonyl chloride → (2R)-2-Hydroxy-4-(6-methoxy-3-oxopyrido[2,3-b]pyrazin-4(3H)-yl)butyl 4-methylbenzensulfonate

Participants

Reaction Steps

In dichloromethane (80 ml) was dissolved 4-[(3R)-3,4-dihydroxybutyl]-6-methoxypyrido[2,3-b]pyrazin-3(4H)-one (4.38 g, 16.51 mmol) and triethylamine (2.76 ml, 19.81 mmol), dimethylamino pyridine (403 mg, 3.30 mmol) and p-toluene sulfonyl chloride (3.46 g, 18.16 mmol) were added thereto under cooling on ice and the mixture was stirred at room temperature for 24 hours. After completion of the reaction, water was added to the reaction solution, which was extracted with dichloromethane. After drying the extract over anhydrous sodium sulfate, the solvent was removed under reduced pressure and the obtained residue was purified by silica gel column chromatography (chloroform/methanol) to yield 4.30 g (62%) of the title compound in the form of an orange oily product.

Provenance & Evidence