反应详情

温度

10 °C

To a solution of 6-(3,5-dimethylbenzyl)-5-ethyl-1-(2-hydroxyethoxymethyl)uracil (0.2 g, 0.6 mmol), N,O-bis(phenoxycarbonyl)hydroxylamine (0.18 g, 0.66 mmol) and triphenylphosphine (0.19 g, 0.66 mmol) in tetrahydrofuran (6 ml) was added dropwise at 0° C. DIAD (diisopropylazodicarboxylate) (145 mg, 0.71 mmol). The reaction medium, concentrated, was subjected successively to two flash column chromatographies on silica gel, the first one using a mixture dichloromethane/methanol 49:1 as eluant and the second one, the mixture ethyl acetate/petroleum ether 2:3. It was thus obtained 6-(2,3-dimethyl-benzyl)-5-ethyl-1-(2-N,O-bis(phenoxycarbonyl)hydroxyaminoethoxymethyl) uracil (0.30 g, 85%), 0.15 g (0.25 mmol) which was dissolved in a ammonia saturated methanolic solution (10 ml) and stirred for 24 h at 10° C. The reaction medium, concentrated, subjected to a flash column chromatography on silica gel (dichloromethane/methanol 19:1) gave an oil which, taken again with ether, gave the 1-(2-N1-hydroxyureidoethoxymethyl)-6-(3,5-dimethylbenzyl)-5-ethyl-uracil (36.6 mg, 36%) in the form of a white solid.

1. customThe reaction medium
2. concentrationconcentrated
3. dissolutionwas dissolved in a ammonia saturated methanolic solution (10 ml)
4. customThe reaction medium
5. concentrationconcentrated
6. customgave an oil which