Didanosine-13C2,15N (2,3-Dideoxyinosine-13C2,15N, ddI-13C2,15N) is the 13C- and 15N-labeled labeled Didanosine (HY-B0249). Didanosine (2,3-Dideoxyinosine, ddI) is a a potent and orally active dideoxynucleoside analogue, and also is a potent nucleoside reverse transcriptase inhibitor. Didanosine shows antiretroviral activity for HIV[1][2][3].