Synthesis, Conformation and Hydrolytic Stability of p¹,p³−Dinucleoside Triphosphates Related to mRNA 5′-cap, and Comparative Kinetic Studies on their Nucleoside and Nucleoside Monophosphate Analogs

Abstract

P¹,P³−Dinucleoside triphosphates, N(5′)G(5′)G, have been prepared in which N is 7-Me-, 7-Et-, 7-Bn, N², 7-diMe- or N²,N², 7-triMe-guanosine. Conformations of the nucleoside moieties have been determined and compared with those of the corresponding nucleoside monophosphates. The hydrolytic stability of the 7-alkylguanine ring has been studied and the origin of the structural effects elucidated by comparative kinetic studies with monomeric nucleoside and nucleotide analogs. The mechanism of the alkaline decomposition has been established Or following the cleavage of 7-methylguanosine by ¹H and ¹³C NMR spectroscopy.