| 摘要 |
<p>PROBLEM TO BE SOLVED: To newly obtain the subject compound by specific plural processes, showing excellent antiviral action on herpes virus, useful as an anti-herpes viral agent. SOLUTION: A 2',3'-dideoxy-pentofuranoside derivative of formula I (R2 is an OH-protecting group) is reacted with a bis(triorganosilyl)-2-thiopyrimidine of formula II (R1 is H or a lower alkyl; R3 to R5 are each an alkyl or an aryl; X is OH or amino; Y is ON or O; Z is an eliminable group) in the presence of a Lewis acid (e.g. tin tetrachloride, etc.) to produce 2',3'-dideoxy-2- thiopyrimidine nucleoside of formula III. The R2 group at the 5'-position of the saccharide part of the compound of formula III is deprotected to give the objective compound of formula IV. The first process is preferably carried out by using an aprotic organic solvent such as dichloromethane in a temperature range from -40 deg.C to a room temperature for 1-15 hours, etc.</p> |
