反应详情

To a solution of 1-(2-O-nitro-3,5-di-O-acetyl-β-D-arabinofuranosyl)-N4 -acetylcytosine (10 g., 24 mmol) in anhydrous methanol (425 ml) under an atmosphere of dry nitrogen was added 1.9N barium methoxide (5 ml., 9.5 meq) in methanol. The reaction mixture was stirred at room temperature under an inert atmosphere for one hour and was then neutralized with a cation exchange resin (90 g., Bio-Rex 70/H+, 100-200 mesh )in the presence of water (5 ml). The resin was separated by filtration and washed with methanol. The combined filtrate and washings were evaporated under reduced pressure to yield crude 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (6.60 g., 95%), which was crystallized from H2O to yield pure 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (5.97 g., 86%): m.p. 151.3°-152.7° C.;

1. customThe resin was separated by filtration
2. washwashed with methanol
3. customThe combined filtrate and washings were evaporated under reduced pressure
4. customto yield crude 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (6.60 g., 95%), which
5. customwas crystallized from H2O