Carbohydrate-protein binding interactions can be greatly amplified using the cluster or multivalent effect. In previous studies, sialylated multibranched L-lysine dendrimers were found to be patent inhibitors of the hemagglutination of human erythrocytes by Influenza viruses. In order to further the understanding of multivalency and its role in carbohydrate-protein interactions, glycoconjugates with differing carbohydrate densities, conformations, and interglycosidic spacings must be prepared. The synthesis and biological testing of structurally similar divergent and tethered alpha-sialodendrimers are presented herein. alpha-Thiosialoside-containing dendrimers scaffolded on an orthogonally protected 3,3’-iminobis(propylamine) core were efficiently prepared via Cbz-protecting group and HOBt/DIC coupling strategies. The potential of these sialodendrimers to cross-link and precipitate Limax flavus lectin (LFA) was confirmed by turbidimetric analysis. When tested in enzyme-linked lectin inhibition assays using human al-acid glycoprotein (orosomucoid) as coating antigen and horseradish peroxidase-labeled LFA for detection di- (31), tetra- (32), octa- (33), and hexadecavalent (34) divergent dendrimers Showed IC50 values of 176, 11.8, 206, and 425 nM while the tethered structures with valencies of four (14), six (20), eight (25), and twelve (30) exhibited IC50 values of 58.7, 16.9, 17.5, and 8.22 nM, respectively. These data represent 3.5 (34) to 182 (30) fold increases in inhibitory potential over monovalent 5-acetamido-5-deoxy-D-glycero-alpha-D-galacto-2-nonulopyranosyl azide used as a standard (IC50 1500 nM). The tethered alpha-sialodendrimers appeared to have structural organizations more suitable than the divergent dendrimers for the solid phase inhibition of the binding of human al-acid glycoprotein to LFA. All alpha-sialodendrimers are currently being evaluated as inhibitors of human erythrocyte hemagglutination by Influenza viruses.