Doravirine-13C,d3 (MK-1439-13C,d3) is the deuterium labeled Doravirine (HY-16767). Doravirine (MK-1439) is a highly specific HIV-1 nonnucleoside reverse transcriptase inhibitor with IC50s of 4.5 nM, 5.5 nM and 6.1 nM against the wild type and K103N and Y181C reverse transcriptase mutants, respectively[1].