Comments on 4-point functions in the CFT/AdS correspondence

We study the four–point function of chiral primaries corresponding to the dilaton–axion sector in supergravity in the $Ad{S}_5$/CFT${}_4$ correspondence. We find relations between some of the supergravity graphs and compute their leading singularities. We discuss the issue of logarithmic singularities and their significance for the OPE structure of the CFT.