Kb. Lesiak et al., THE SOLID-PHASE SYNTHESIS OF 2'-5'-LINKED OLIGORIBOADENYLATES CONTAINING 8-BROMOADENINE, Applied biochemistry and biotechnology, 67(1-2), 1997, pp. 33-44
To increase the accessibility of 8-bromo-2',5'-oligoadenylates, we dev
eloped a synthesis of 2'-5'-linked oligoriboadenylates containing vary
ing numbers of 8-bromoadenosine residues based on the use of a CPG-LCA
solid support and the phosphoramidite approach. Although N-6-benzoyl
protection was satisfactory for incorporation of nonmodified adenine r
esidues into 2',5'-oligonucleotides, the effective incorporation of 8-
bromoadenine into such 2',5'-linked oligomers required use of a non ac
yl protecting group. Amidine protection of the purine exocyclic amino
function proved compatible with all aspects of the phophoramidite appr
oach and with the hydroxyl protection groups employed.