445417-49-2Relevant articles and documents
Chemical Synthesis of Oligoribonucleotide (ASL of tRNALys T. brucei) Containing a Recently Discovered Cyclic Form of 2-Methylthio-N6-threonylcarbamoyladenosine (ms2ct6A)
Debiec, Katarzyna,Matuszewski, Michal,Podskoczyj, Karolina,Leszczynska, Grazyna,Sochacka, Elzbieta
, (2019)
The synthesis of the protected form of 2-methylthio-N6-threonylcarbamoyl adenosine (ms2t6A) was developed starting from adenosine or guanosine by using the optimized carbamate method and, for the first time, an isocyanate route. The hypermodified nucleoside was subsequently transformed into the protected ms2t6A-phosphoramidite monomer and used in a large-scale synthesis of the precursor 17nt ms2t6A-oligonucleotide (the anticodon stem and loop fragment of tRNALys from T. brucei). Finally, stereochemically secure ms2t6A→ms2ct6A cyclization at the oligonucleotide level efficiently afforded a tRNA fragment bearing the ms2ct6A unit. The applied post-synthetic approach provides two sequentially homologous ms2t6A- and ms2ct6A-oligonucleotides that are suitable for further comparative structure–activity relationship studies.
Synthesis of the tRNALys,3 anticodon stem-loop domain containing the hypermodified ms2t6A nucleoside
Bajji, Ashok C.,Davis, Darrell R.
, p. 5352 - 5358 (2007/10/03)
The synthesis of a protected form of the hypermodified nucleoside, N-[(9-β-D-ribofuranosyl-2- methylthiopurin-6-yl)carbamoyl]threonine, (ms2t6A) is reported. The hypermodified nucleoside was subsequently elaborated to the protected nucleoside phosphophoramidite using a protecting group strategy compatible with standard RNA oligonucleotide chemistry. The phosphoramidite reagent was then used to synthesize the 17-nucleotide RNA hairpin having the sequence of the anticodon stem-loop (ASL) domain of human tRNALys,3, the primer for HIV-1 reverse transcriptase. Introduction of the modification at position 37 of the tRNA ASL modestly decreases the thermodynamic stability of the RNA hairpin as has been seen previously for the prokaryotic t6A nucleoside lacking the 2-methylthio substituent. 2D NOESY NMR spectra of the ms2t6A containing tRNA ASL indicate that the threonyl side chain adopts a conformation similar to that seen in the solution structure of the analogous t6A containing E. coli tRNALys, despite the presence of the bulky methylthio group. This synthetic approach allows for site-specific incorporation of the hypermodified nucleoside and should facilitate future studies directed at understanding the roles of nucleoside modification in modulating the stability and specificity of biologically important RNA-RNA interactions. Our synthesis of the ms2t6A containing RNAs demonstrates that this methodology is suitable for obtaining quantities of RNA required for structural studies of the HIV primer tRNA.
