2'-O-Methyluridine-d3 is deuterium labeled 2'-O-Methyluridine (HY-W011824). 2-O-Methyluridine is a modified nucleoside that can be found in T. thermophile tRNA. 2-O-Methyluridine can be incorporated into siRNA targeting the gene encoding apolipoprotein B, which decreases ApoB protein levels in HepG2 and prevents IFN-alpha production in isolated human PBMCs. 2-O-Methyluridine level in serum is decreased in patients with breast cancer[1][2][3].