STEREOSELECTIVE SYNTHESIS METHOD FOR 4'-SUBSTITUTED NUCLEOSIDE DERIVATIVE

摘要

Current synthesis methods for 4'-substituted nucleoside derivatives include a step in which stereoisomers are produced and therefore have problems such as decreased yield and complication of a refinement step. Thus, a synthesis method has been sought that is simpler and does not produce stereoisomers. The present invention provides a synthesis method for a 4'-substituted nucleoside intermediate represented by formula (6), the method comprising the following steps 1 through 3: step 1 in which a compound of formula (3) is used as a starting raw material, and a nucleophile is made to act on the compound of formula (3) to obtain the compound of formula (4) in which a substituent group has been stereoselectively introduced; step 2 in which the compound of formula (4) is hydrolized to obtain the compound of formula (5); and step 3 in which the compound of formula (5) is held in acidic conditions to obtain the compound represented by formula (6). In the formulas, R₁ indicates a protective group of a hydroxyl group, Me indicates a methyl group, and X indicates a substituent group.