A method of making nucleoside 1, which has a 3-hydrocarbyl-5-fluoro-5-(hydroxy-methyl)tetrahydrofuran-3,4-diol ring system, where hydrocarbyl group R1 is lower alkyl, lower alkenyl, or lower alkynyl and R2 may be an adenine moiety having an exocyclic amino group protected as an imidodicarbonate or as a carbamate. Nucleoside 1 is prepared from an intermediate 4 by adding iodine fluoride across the exocyclic double bond to produce a 5-fluoro-5-iodomethyl derivative 5. The iodine atom is displaced with a carboxylic acid nucleophile in the presence of an oxidizing agent to produce a 5-fluoro-5-(acyloxy)methyl ester derivative 7, where R3 is an acyl group. Ester 7 may be converted into compound 1 by cleavage of the ester.
制备核苷1的方法,核苷1具有一个3-羟基烷基-5-
氟-5-(羟甲基)
四氢呋喃-3,4
-二醇环系统,其中烃基R1为较低的烷基、较低的烯基或较低的炔基,R2可能是具有外环
氨基团被保护为酰胺二
碳酸酯或为
碳酸酯的
腺嘌呤基团。通过在外环双键上加入
碘氟化物来从中间体4制备核苷1,以产生一个5-
氟-5-
碘甲基衍
生物5。在氧化剂存在下,
碘原子被
羧酸亲核试剂取代,产生一个5-
氟-5-(酰氧基)甲基酯衍
生物7,其中R3是酰基。酯7可以通过酯的裂解转化为化合物1。