Table 2. Effects of R¹ Substitution and Quinoline Modifications to Amino-oxadiazoles on IDO1 Inhibitory Activity, in Vitro Metabolic Stability, and PXR Activation.

^aData reported as average of test results (N = 2 unless otherwise noted). See Supporting Information for a description of assay conditions.

^bFraction of the parent compound (0.5 μM) remaining after a 10 min incubation with 1 mg/mL of human, mouse, and rat liver microsomes (HLM, MsLM, RLM).

^cThe pregnane X receptor (PXR) transactivation activity was measured by comparing to activation with rifampicin to assess the potential for induction of cytochrome P450 (CYP) 3A4 (Et = ethyl, MOM = methoxymethyl, EOM = ethoxymethyl).