21052-18-6Relevant articles and documents
Synthesis, base pairing and structure studies of geranylated RNA
Wang, Rui,Vangaveti, Sweta,Ranganathan, Srivathsan V.,Basanta-Sanchez, Maria,Haruehanroengra, Phensinee,Chen, Alan,Sheng, Jia
, p. 6036 - 6045 (2016)
Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. 2-Thiouridine geranylation is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, such as Escherichia coli, Enterobacter aerogenes, Pseudomonas aeruginosa and Salmonella Typhimurium. The geranylated residues are located in the first anticodon position of tRNAs specific for lysine, glutamine and glutamic acid. This big hydrophobic terpene functional group affects the codon recognition patterns and reduces frameshifting errors during translation. We aimed to systematically study the structure, function and biosynthesis mechanism of this geranylation pathway, as well as answer the question of why nature uses such a hydrophobic modification in hydrophilic RNA systems. Recently, we have synthesized the deoxy-analog of S-geranyluridine and showed the geranylated T-G pair is much stronger than the geranylated T-A pair and other mismatched pairs in the B-form DNA duplex context, which is consistent with the observation that the geranylated tRNAGluUUC recognizes GAG more efficiently than GAA. In this manuscript we report the synthesis and base pairing specificity studies of geranylated RNA oligos. We also report extensive molecular simulation studies to explore the structural features of the geranyl group in the context of A-form RNA and its effect on codon-anticodon interaction during ribosome binding.
Structural modifications of UMP, UDP, and UTP leading to subtype-selective agonists for P2Y2, P2Y4, and P2Y6 receptors
El-Tayeb, Ali,Qi, Aidong,Nicholas, Robert A.,Müller, Christa E.
supporting information; experimental part, p. 2878 - 2890 (2011/06/24)
A large series of derivatives and analogues of the uracil nucleotides UMP, UDP, and UTP with modifications in various positions of the uracil moiety and/or the phosphate groups were synthesized and evaluated at human P2Y2, P2Y4, and P2Y6 receptors. 2-(Ar)alkylthio substitution of UMP and UDP was best tolerated by the P2Y2 receptor. 2-Phenethylthio-UMP (13e) showed an EC50 value of 1.3 μM at P2Y2 and >70-fold selectivity versus P2Y4 and P2Y 6 receptors. Substitution of the 2-keto group in UMP by NH (13g, iso-CMP) resulted in the first potent and selective P2Y4 agonist (EC50 4.98 μM, >20-fold selective vs P2Y2 and P2Y6). In contrast, replacement of the 2-keto function in UDP by NH yielded a potent P2Y2 agonist (12g, iso-CDP, EC50 = 0.604 μM, >100-fold selective). In an attempt to obtain metabolically stable UTP analogues, β,γ-dichloro- and β,γ-difluoro-methylene-UTP derivatives were synthesized. The triphosphate modifications were much better tolerated by P2Y2, and in some cases also by P2Y6, than by P2Y4 receptors. 4-Thio-β,γ-difluoromethylene-UTP (14g) was a potent P2Y2 agonist with an EC50 value of 0.134 μM and >50-fold selectivity. N3-Phenacyl-β,γ-dichloromethylene- UTP (14b) proved to be a potent P2Y6 receptor agonist (EC 50 0.142 μM) with high selectivity versus P2Y4 (50-fold) and moderate selectivity versus P2Y2 receptors (6-fold).
Transformations of thiopyrimidine and thiopurine nucleosides following oxidation with dimethyldioxirane
Saladino, Raffaele,Mincione, Enrico,Crestini, Claudia,Mezzetti, Maurizio
, p. 6759 - 6780 (2007/10/03)
A general and convenient method for the synthesis of several pyrimidine and purine nucleosides by selective oxidation of thionucleosides with dimethyldioxirane is reported. Thioketo moieties in the C-4 position of the pyrimidine ring, and in the C-6, and C-8 positions of the purine ring are the domain of oxidative nucleophilic substitution. Thioketo moieties in the C-2 position of both purine and pyrimidine rings are the domain of desulfurization or formation of disulfides.
