Patent ID: 8765933

Claim:
A process of preparing a β-nucleoside compound formula (I): wherein each of R 1 and R 2 , independently, is H, alkyl, aryl, aralkyl, alkyldiarylsilyl, trialkylsilyl, triarylsilyl, RC(O)—, RR′NC(O)—, ROC(O)—, RC(S)—, RR′NC(S)—, or ROC(S)—; each of R and R′, independently, being H, alkyl, aryl, cycloalkyl, heterocycloalkyl, or heteroaryl; each of R 3 and R 4 , independently, is H or fluoro; and B is in which R 5 is H, alkyl, or aryl; R 6 is H, alkyl, alkenyl, halo, or aryl; X is N or C—R″, R″ being H, alkyl, alkenyl, halo, amino, or aryl; and Y is an amino protecting group; the process comprising reacting, in the presence of an oxidizing agent, a tetrahydrofuran compound of formula (II): wherein R 1 , R 2 , R 3 , and R 4 are as defined above and L is chloro, bromo, or iodio, with a nucleobase derivative of the following formula: wherein R 5 , R 6 , X, and Y are as defined above and Z is a hydroxyl protecting group; in which the oxidizing agent is Br 2 , H 2 O 2 , O 2 , Cl 2 , O 3 , F 2 , 3-chloroperbezoic acid, azobisisobutyronitrile, 2,2,6,6-tetramethylpiperidine 1-oxyl, or a salt including an ion selected from the group consisting of Fe 3+ , Ce 4+ , Au 3+ , Co 3+ , NO 3 − , MnO 4 − , Cr 2 O 7 2− , HSO 5 − , and S 2 O 8 2− .