PITFALLS IN THE SYNTHESIS AND BIOLOGICAL EVALUATION OF SIALYL-LEWIS(X) MIMETICS AS POTENTIAL SELECTIN ANTAGONISTS

The lower molecular weight analog 12 of sialyl Lewis(X) was prepared a nd effected equal binding affinity to E- and P-selectin compared to th e parent tetrasaccharide. If 12 was prepared using acidic ion exchange resins, false positive test were produced, especially binding to P-se lectin seemed to be considerably enhanced. Traces of polyanions releas ed from the resins which are difficult to detect by routine analysis w ere identified to be highly potent selectin inhibitors, probably by th eir action on a non-carbohydrate binding site. (C) 1997, Elsevier Scie nce Ltd.