Comparison of N,N′-diarylsquaramides and N,N′-diarylureas as antagonists of the CXCR2 chemokine receptor

N,N′-diarylsquaramides were prepared and evaluated as antagonists of CXCR2. The compounds were found to be potent and selective antagonists of CXCR2. Significant differences in SAR were observed relative to the previously described N,N′-diarylurea series.