Indinavir-13C4,15N (MK-639 (free base)-13C4,15N) is 13C and 15N labeled Indinavir. Indinavir (MK-639 free base) is an orally active and selective HIV-1 protease inhibitor with a Ki of 0.54 nM for PR. Indinavir exhibits anticancer activity by inhibiting the activation of MMPs-2 hydrolysis, anti-angiogenesis and inducing apoptosis. Indinavir is also a SARS-CoV 3CLpro inhibitor[1][2][3][4].