Solid-phase synthesis of oligodeoxyribonucleotides without base protection utilizing O-selective reaction of
Natsuhisa Oka1, Yukihiro Maizuru, Mamoru Shimizu
1Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan.
Abstract:
A study on the development of a novel method to synthesize oligodeoxyribonucleotides without base protection is described. We found that nucleoside 3'-O-oxazaphospholidine derivatives exclusively react with the hydroxy group of nucleosides in the presence of unprotected nucleobase amino groups. Since the O-chemoselectivity of the oxazaphospholidine derivatives is likely due to their ring structure, which allows the regeneration of the oxazaphospholidine derivatives from the corresponding base phosphitylation adducts via an intramolecular recyclization, the method is expected to be compatible with any kinds of acidic activators.
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