| 摘要 |
<p>PROBLEM TO BE SOLVED: To simply obtain the subject compound for phosphorothioate oligonucleotide intermediate by allowing a nucleoside derivative to react with a thiophosphoryl compound and an alcohol in order, then removing the phosphoric acid-protecting group. SOLUTION: A nucleoside derivative of formula I [B is (protected) nucleic acid base; R1 is a protecting group for hydroxyl group; R2 and R3 are each H, (protected) hydroxyl group where at least one is hydroxyl group] is allowed to react with a thiophosphoryl compound as thiophospho-tris(triazolide), further with an alcohol represented by the formula: HO-R4 (R4 is phosphoric acid- protecting group) as ethylenecyanohydrin. Then, a deprotecting agent (M) as triethylamine is used to remove a part of the phosphoric acid-protecting group (R4 ) to prepare the objective phosphorothioate diester of formula II (M is deprotecting agent) that is useful as a starting substance for synthesizing phosphorothioate oligonucleotide in the one-pot manner according to the phosphoric triester process.</p> |
