Synthesis of the Phosphoramidite Derivatives of 2‘-Deoxy-2‘-C-α-methylcytidine and 2‘-Deoxy-2‘-C-α-hydroxymethylcytidine: Analogues for Chemical Dissection of RNA's 2‘-Hydroxyl Group

Oligonucleotides containing 2'-C-α-methyl and 2'-C-α-hydroxymethyl modifications enable strategies for delineation of the distinctive role fulfilled by the 2'-hydroxyl group in RNA structure and function. Synthetic routes to the phosphoramidite derivatives of 2'-deoxy-2'-C-α-methylcytidine (14%, 15 steps) and 2'-deoxy-2'-C-α-hydroxymethylcytidine (19%, 10 steps) from methyl 3,5-di-O-(4-chlorobenzyl)-α-d-ribofuranoside are developed.