N6-Methyladenosine-13C4 (6-Methyladenosine-13C4, N-Methyladenosine-13C4) is 13C-labeled N6-Methyladenosine (HY-N0086). N6-Methyladenosine is the most prevalent internal (non-cap) modification present in the messenger RNA (mRNA) of all higher eukaryotes. N6-Methyladenosine can modifies viral RNAs and has antiviral activities.