Table 1. NOD2 Agonistic Activities of Compounds with Structural Modifications of the MurNAc Mimetic, the Central Amino Acid, and the Effect of Chain Elongation by l-Lysine.

^aSEAP activities were measured in NOD2-specific HEK-Blue cell supernatants after incubation for 18 h with MDP (2 μM) or the compounds of interest (2 μM). The data are shown as fold increases of NF-κB transcriptional activity relative to the negative control (0.1% DMSO) and are expressed as mean ± SEM of at least two independent experiments.

^bEC₅₀ values are expressed as mean ± SEM of at least two independent experiments with 7 or 8 concentrations used (from 1 nM to 20 μM).

^cMixture of two diastereomers (R,R and S,S configurations of substituents on the cyclopropyl ring).

^dIt was not possible to conclusively determine the absolute stereochemical configurations of 29a and 29b; however, both contained a trans-configured cyclopropyl ring (R,R and S,S configurations).