title: Methylation of desmethyl analogue of Y nucleosides. Wyosine from guanosine.
abstract: Wyosine la, one of the fluorescent hypermodified Y nucleosides found in tRNAsPhe, was synthesized chemically from its biogenetic precursor guanosine 2. The route involved transformation of 2 into the tricyclic structure 3a and subsequent methylation at N-4. The major products of various methylation procedures were isomers of wyosine, methylated at N-5 (3b) or at N-1 (4). Mesoionic compound 4 is a new analogue of 7-methylguanosine 5, modified nucleoside occurring in the unique positions in transfer, messenger and ribosomal RNAs. The chromatographic and spectral characteristics of wyosine and its isomers is given.
mesh_terms: D006151:Guanosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D007202:Indicators and Reagents; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008722:Methods; D008745:Methylation; D012313:RNA / Q000032:analysis; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007202:Indicators and Reagents; D006151:Guanosine; C012100:wyosine; D012313:RNA