Synthesis of the 3′-terminal dinucleotide of tRNA aminoacylated with the unnatural ω-thioaspartic acid

[Display omitted] Our objective is to incorporate the non-natural ω-thioaspartic acid (SAsp) into proteins within a cell-free translation system and utilize the thiocarboxylic acids in side chains as handles for post-translational chemical modifications. As the initial step, in this study, we synthesized a protected dinucleotide (pdCpA) aminoacylated with SAsp, corresponding to the 3′-end of tRNA. Furthermore, indications suggest that the aminoacylated pdCpA can be deprotected through acid treatment.