There is no universal mechanism for the cleavage of RNA model compounds in the presence of metal ion catalysts

: Korhonen H, Koivusalo T, Toivola S, Mikkola S

Publisher: ROYAL SOC CHEMISTRY

: 2013

: Organic and Biomolecular Chemistry

: ORGANIC & BIOMOLECULAR CHEMISTRY

: ORG BIOMOL CHEM

: 48

: 11

: 48

: 8324

: 8339

: 16

: 1477-0520

DOI: https://doi.org/10.1039/c3ob41554f

The transesterification of uridine 3'-phosphodiesters with a wide range of leaving group alcohols has been studied in the presence of monometallic and bimetallic complexes. The catalysis of isomerization of the phosphodiester bond was studied with a nucleoside 3'-phosphonate as a substrate. The results obtained are consistent with a step-wise mechanism, where metal ions are able to enhance both the nucleophilic attack and the departure of the leaving group. The mechanism of the catalysis depends on the acidity of the catalyst and of the leaving group alcohol: a change from general base catalysis to general acid catalysis is proposed. Catalysis of the isomerization requires efficient stabilization of the phosphorane by strong interactions with the catalyst. Catalytic strategies utilised by bimetallic complexes are also briefly discussed.