2-Thiouridine (s2U) is a naturally occurring modified nucleobase present in transfer RNAs that stabilizes U:A base pairing while modestly destabilizing U:G wobble interactions. 2-Thiouridine influences codon–anticodon recognition, translational accuracy, and RNA conformational dynamics, and is extensively used in studies of nucleic acid structure, RNA biology, and the engineering of functional RNA-based biomolecules.

In viral replication assays, 2-Thiouridine inhibited the replication of several positive-strand RNA viruses (DENV2, ZIKV, SARS-CoV, SARS-CoV-2) with effective concentrations ranging from 0.625 to 40 μM [1].

In DENV2-infected mice, oral administration of 2-thiouridine (50-150 mg/kg, twice daily) prolonged survival and reduced viral RNA loads in the serum and spleen. In SARS-CoV-2 mouse models, treatment via intravenous injection (2-20 mg/kg, once daily) or high-dose oral administration (300 mg/kg, twice daily) for 5 days resulted in increased survival rates, lower lung viral titers, and reduced levels of inflammatory cytokines [4].

H2O: 8 mg/mL (30.74 mM), Sonication is recommended.

Ethanol: 2 mg/mL (7.68 mM), Sonication is recommended.

PBS (pH 7.2): 5 mg/mL (19.21 mM), Sonication is recommended.

DMF: 10 mg/mL (38.42 mM), Sonication is recommended.

DMSO: 40 mg/mL (153.69 mM), Sonication is recommended.