Enantio-oligodeoxyribonucleotides.

As a sugar-modified oligonucleotide, a hexamer of 9-(2-deoxy-beta-L-erythro-pentafuranosyl)-9H-purin-6-amine, [L-(dAp)5dA], was synthesized by triester method. The L-hexamer was resistant to bovine spleen phosphodiesterase. UV absorption studies indicated that L-hexamer formed a complex with poly U but not with poly dT at 0 degrees C. It was assumed that enantio-DNA's possese the ability to distinguish complementary RNA from DNA.