DMTr-4'-Me-U-CED-TBDMS phosphoramidite (DMTr-4'-Methyluridine-CED-TBDMS phosphoramidite), a dye reagent for oligonucleotide labeling, can be used for the research of applications in RNA therapeutics, RNA aptamers , and ribozymes for elucidating RNA structure. DMTr-4'-Me-U-CED-TBDMS phosphoramidite represents a probe with wide utility for elucidation of RNA structure.