| 摘要 |
1 - (21, 31 - Anhydrolyxofuranosyl) - 2 - ketopyrimidine nucleosides are prepared by reacting the corresponding 51-O-benzoyl derivatives with a nitrogenous base having a dissociation constant in water, Kb, of 1.0 x 10-3 to 1.0 x 10-9 in the presence of an inert solvent at - 20 DEG to 25 DEG C. The 2-ketopyrimidine group may be derived from uracil, 5-fluorouracil, thymine, cytosine or azauracil. Suitable nitrogenous bases include primary and secondary amines, ammonia and hydrazine and suitable solvents include alkanols. |
