Azobisisobutyronitrile → 1-[(2S,4R,5R)-4-allyl-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)tetrahydrofuran-2-yl]propyl benzoate

Participants

Reaction Conditions

Reaction Steps

A mixture of 1-[(2S,4R,5R)-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)-4-phenoxycarbothioyloxy-tetrahydrofuran-2-yl]propyl benzoate (compound 26e, 1.14 g, 2.0 mmol), 2,2′-azobisisobutyronitrile (168 mg, 1 mmol) and allyl(tributyl)stannane (3.08 mL, 10 mmol) in anhydrous toluene (15 mL) was degassed with argon and then heated with stirring at 80° C. for 4 hours. The resulting mixture was stirred with saturated aqueous NH4F at room temperature for 2 hours and extracted with DCM twice. The combined organic layers were dried over Na2SO4, concentrated in vacuo and the residue was purified by column chromatography on silica gel (eluting with 1:3 EtOAc in petroleum ether) to afford 820 mg of 1-[(2S,4R,5R)-4-allyl-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)tetrahydrofuran-2-yl]propyl benzoate (compound 26f) as a brown solid. MS obsd. (ESI+) [(M+H)+]: 457.

Provenance & Evidence