Deoxythymidine-5-triphosphate-15N2 (dTTP-15N2) dilithium is 15N labeled Deoxythymidine-5-triphosphate (HY-138615). Deoxythymidine-5-triphosphate (dTTP) is one of the four nucleoside triphosphates. Deoxythymidine-5-triphosphate (dTTP) is used in the synthesis of DNA.