Patent ID: 6891036

Claim:
A process for the preparation of ribofuranose derivatives of formula (I): wherein R and R′, equal or different from each other, are acyl groups chosen between C1-C6 alcanoyl groups and C7-C13 aroyl groups, optionally substituted with one or more substituents selected from the group consisting of alogens, alkyl groups C1-C4, alkylamino groups C1-C4, alkylocy groups C1-C4 and nitro groups; comprising the following steps: 1) selective acylation in positions 3 and 5 of the lactone of formula (II) by reaction with an acyl chloride R′Cl selected according to the acyl group that has to be introduced in the product of formula (II) to abtain the 3,5-diacyl derivative of formula (III): wherein R′ is as described above; 2) reduction of 3,5-diacyl lactone of formula (III) with a wherein R′ is as described above; 3) acylation of 3,5-diacyl ribofuranose of formula (IV) to obtain the product of formula (I) wherein R and R′ are as described above, said process being characterised in that the reduction in step 2) is carried out at pH ranging between 5 and 9 by using a borohydride of an alkaline metal as reducing agent.