| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a new 3'-4' crosslinked nucleoside useful as an intermediate for producing an oligonucleotide analogue used as an antiviral drug, an anti- sense or anti-gene drug, or the like, which are stable and excellent. SOLUTION: This new compound is represented by formula I (R1 and R2 are each H, phosphate group; A is a 1-4C alkylene; B is purin-9-yl, or the like) and is preferably 3'-O,4'-C-ethylene-5-methyluridine. The compound of formula I is obtained by reacting a compound of formula II (X and Y are each a protecting group) with an eliminable group-introducing reagent such as p- toluenesulfonylchloride, an acid anhydride such as acetic anhydride and a trimethylsilylation product corresponding to a purine or pyrimidine capable of containing a desired substituent in order, and then eliminating a protecting group Y of a produced compound of formula III (R9 is a group for forming an eliminable group together in association with oxygen; Z is an acryl; B1 is purin-9-yl, or the like) and simultaneously performing cyclization reaction of a deprotected 3'OH and a group of OR9.</p> |
