Structure-activity relationships of 6-hydroxy-7-methoxychroman-2-carboxylic acid N-(substituted)phenylamides as inhibitors of nuclear factor-kB activation

A series of 6-hydroxy-7-methoxychroman-2-carboxylic acid N-substitutedphenylamides (2a-n) were synthesized and their ability to inhibit nuclear factor-kappaB activity was evaluated in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. While compounds bearing -OH, or -OCH3 substituents were inactive, compounds with -CH3, -CF3, or -Cl substituents were potent inhibitors (IC50: 6.0-60.2 microM). The most active compound, 2n, contained a 4-Cl substituent on the phenyl ring and was four times more potent than the compound KL-1156.