9-(Tetrahydro-5-methyl-2-furyl)adenine (Didanosine EP Impurity H) is an impurity of Didanosine (D440950), which used as an antiviral agent. Classed as an anti-retroviral drug used in the treatment of HIV in ART therapy, it also may increase acetaminophen related hepatotoxicity by enhancing mitochrondrial dysfunction (2).
