Decitabine-13C5 (5-Aza-2-deoxycytidine-13C5) is 13C labeled Decitabine. Decitabine (NSC 127716) is an orally active deoxycytidine analogue antimetabolite and a DNA methyltransferase inhibitor. Decitabine incorporates into DNA in place of cytosine can covalently trap DNA methyltransferase to DNA causing irreversible inhibition of the enzyme. Decitabine induces cell G2/M arrest and cell apoptosis. Decitabine has potent anticancer activity[1][2].