利巴韦林杂质48

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: The protective group at C-1 of the ribofuranose is made in the immediately preceding step. Benzoyl chloride is added to a 5° C. solution of 2,3,5-tri-O-benzoyl-2-C-methyl-D-ribofuranose in approximately a 2:1 molar ratio, along with DMAP and TEA in anhydrous DME. The reaction is stirred and allowed to run overnight, after which it is quenched with ice water and aqueous sodium carbonate solution. THF is then removed, and the mixture is extracted with ethyl acetate. Washing, drying and solvent removal produces a thick, oily product. The latter has added to it tert-butyl methyl ether, heptane and water, and is stirred for approximately 2 hours at about 20° C. The final product, 1,2,3,5-tetra-O-benzoyl-2-C-methyl-β-D-ribofuranose, is obtained in 52% yield and greater than 98% purity, after washing and vacuum drying (see FIG. 1, compound 4, Scheme 1). after which it is quenched with ice water and aqueous sodium carbonate solution THF is then removed the mixture is extracted with ethyl acetate Washing drying solvent removal produces a thick, oily product is stirred for approximately 2 hours at about 20° C