We have identified a novel series of substituted N,N'-diarylurea p38α inhibitors. The inhibitory activity of the target compounds against the enzyme p38α, MAPKAPK2 in BHK cells, TNF-α release in LPS-stimulated THP-1 cells and p38α binding experiments were tested. Among these compounds, 25a inhibited the p38α enzyme with an IC50 value of 0.47 nM and a KD value of 1.54 × 10(-8) and appears to be the