Adhesion of leukocytes to endothelium plays an important role in inflammation-associated diseases.Our previous studies showed that multivalent lactosides were able to inhibit this process.Using 2-azide-l,3-propandiol and glutamic acid as spacers,we synthesized divalent lactoside An-2 and tetravalent lactoside Gu-4 by means of convergent method.These two compounds displayed high anti-adhesive activity and showed therapeutic effect in rats with severe burn shock.In addition, investigation of the anti-adhesion biological mechanism using labeled compounds YAn-2 and YGu-4 demonstrated that the target of multivalent lactosides was CD11b,theβ2 integrin subunit,on the surface of leukocytes.In this paper,the synthesis of these two new multivalent lactosides as well as their fluorescein-labeled and biotin-labeled compounds is reported.