The general procedure for the synthesis of N-(9-((2R,3R,4R,5R)-3-fluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-9H-purin-6-yl)benzamides from the compound (CAS:146954-64-5) is as follows: araadenosine (10) first undergoes a methanosilicate-protected hydroxyl group, followed by a reaction at position N6 Benzoylation reaction was carried out. Next, the methylsilyl protecting group is removed using ammonium hydroxide, and then THP protecting groups are introduced by the reaction to protect the 3'- and 5'-hydroxyl groups. Treatment with dihydropyran (DHP) in the presence of a catalytic amount of p-toluenesulfonic acid (pTsOH) yielded protected araadenosine (11). Subsequently, the remaining 2'-hydroxyl group was reacted with trifluoromethanesulfonic anhydride to convert to trifluoromethanesulfonate, and the intermediate was directly reacted with tetrabutylammonium fluoride (TBAF) without purification for fluoride substitution to give compound 12. removal of the THP protecting group by acid-catalyzed methanolysis gave the protected fluoroadenosine intermediate.13 Next, selective methylsulfonylation was carried out on the 5'-hydroxyl group reaction, followed by reaction with BOC-protected diamine, yielded compound 14.Finally, the benzoyl protection on N6 was removed by aminolysis, followed by acid-catalyzed carbamate cleavage to give the target compound No.1.
