Nucleoside modifications

Although several methods are used to aminate heterocyclic aromatic hydroxy-N-heterocycles [36], some additional, special, amination procedures are used for nucleoside modification. When we planned to synthesize a series of N -substituted cytidines 5 starting from uridine 1 we considered known classical methods, which imply (Scheme 4.14) ... 

As mentioned in the Introduction, we are especially interested in the effect of nucleoside modifications on RNA structure. The equilibrium sequences introduced above were selected for this reason. The position of the conformational equilibrium of the sequence constructs is expected to be highly sensitive to chemical alteration, e.g. methylation of nucleobases. 

Much remains to be learned about the role of nucleoside modification in ribosomal RNA, but the observation that modifications are clustered in the functionally important regions of the ribosome supports the hypothesis that modifications are used to fine-tune ribosomal function. ... 

B. A. Wojtczak, A. Andrysiak, B. Gruner, Z. J. Lesnikowski, Chemical ligation —A versatile method for nucleoside modification with boron clusters, Chem. Eur. J., 2008,14, 10675-10682. 

Nucleoside Modifications 10.1.1.1 Nucleoside Analogs as Potential Drugs... 

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