Linker phosphoramidite reagents for oligonucleotide synthesis on underivatized solid-phase supports

Linker phosphoramidite reagents containing a protected nucleoside with a cleavable 3′-ester linkage to either succinic acid, diglycolic acid, or hydroquinone-O,O′-diacetic acid (Q-Linker) allow the 3′-terminal nucleoside of an oligonucleotide sequence to be attached to underivatized ‘Universal’ amino or hydroxyl supports. After solid-phase oligonucleotide synthesis, treatment with NH4OH cleaves the 3′-ester link to the support and produces oligonucleotides with only 3′-OH ends. No changes to existing phosphoramidite synthesis cycles, cleavage, or deprotection methods are required.