[N,1-(15)N2]-2'-deoxyadenosines.

An efficient route to deoxyadenosine derivatives labeled on both the amino group and nitrogen 1 is uncovered. First, 3‘,5‘-di-O-acetyl-2‘-deoxy-1-(2-nitrobenzenesulfonyl)inosine (2a) and only 1.1 equiv of 15NH4Cl are used for labeling position 1 (1a*) through the isolation of the open intermediate and its cyclization with DBU in anhydrous CH3CN. Inosine 1a* is then converted to [N,1-15N2]-3‘,5‘-di-O-acetyl-N6-benzoyl-2‘-deoxyadenosine (5a**, the precursor of 6a**) via a Pd/dppf-catalyzed chloride-to-benzamide replacement, by using again only 1.1 equiv of the labeling source.