2-thio PAF is an isosteric analog of PAF. It is also a synthetic analog of PAF which contains an acetyl group attached by a thioester bond at the sn-2 position. It functions as a PAF receptor agonist, and its potency is comparable to PAF C-18 in rabbit platelet aggregation, and to PAF C-16 in the activation of guinea pig macrophages. 2-thio PAF is a substrate for lysophospholipase II and for PAF-AH, and is the substrate used in Cayman’s PAF-AH Assay Kit .