Reaction of 2,3,4-tri- O-acetyl-6- O-(bromoacetyl)-α- d-galactopyranosyl bromide ( 2) with allyl 2,3,4-tri- O-acetyl-β- d-galactopyranoside gave allyl O-[2,3,4-tri- O-acetyl-6- O-(bromoacetyl)-α and β- d-galactopyranosyl]-(1→6)-2,3,4-tri- O-acetyl-β- d-galactopyranoside, 4 (4%) and 5 (88%), respectively. Selective removal of the bromoacetyl group from 5 gave allyl O-(2,3,4-tri- O-acetyl-β- d-galactopyranosyl)-(1→6)-2,3,4-tri- O-acetyl-β- d-galactopyranoside ( 6), which, after condensation with 2,3,4,6-tetra- O-acetyl-α- d-galactopyranosyl bromide ( 1) yielded both allyl O-(2,3,4,6-tetra- O-acetyl-α- and β- d-galactopyranosyl)-(1→6)- O-(2,3,4-tri- O-acetyl-β- d-galactopyranosyl)-(1→6)-2,3,4-tri- O-acetyl-β- d- galactopyranoside, 7 (10%) and 8 (70%), respectively. When 6 was condensed with 2, allyl O-[2,3,4-tri- O-acetyl-6- O-(bromoacetyl)-β- d-galactopyranosyl]-(1→6)- O-(2,3,4-tri- O-acetyl-β- d-galactopyranosyl)- (1→6)-2,3,4-tri- O-acetyl-β- d-galactopyranoside (75%) was obtained. This was selectively O-de(bromoacetyl)ated to yield the nonaacetate, which was condensed with bromide 1 to give allyl O-(2,3,4,6-tetra- O-acetyl-α- and -β- d-galactopyranosyl)-(1→6)- O-(2,3,4-tri- O-acetyl-β- d-galactopyranosyl)-(1→6)- O-(2,3,4-tri- O-acetyl-β- d- galactopyranosyl)-(1→6)-2,3,4-tri- O-acetyl-β- d-galactopyranoside, 14 (4%) and 15 (70%). Epoxidation of the allyl group of 8 and 15 with m-chloroperoxybenzoic acid, and removal of the acetyl protecting groups with sodium methoxide, gave, respectively, 2,3-epoxypropyl O-β- d-galactopyranosyl-(1→6)- O-β- d-galactopyranosyl-(1→6)-β- d-galactopyranoside ( 17) and the corresponding tetrasaccharide 19. Sequential acetylation and O-debenzylation of 6- O-benzyl- d-galactose, followed by coupling of the product with bromide 1, yielded O-(2,3,4,6-tetra- O-acetyl-β- d-galactopyranosyl)-(1→6)-1,2,3,4-tetra- O-acetyl-β- d-galactopyranose ( 12). Conversion of 12 into the bromide by treatment with bromotrimethylsilane, and the condensation of the product with nucleophile 6 also gave the β-linked tetrasaccharide 15 of this series. Epoxidation of the allyl group, followed by removal of acetyl blocking groups in the latter compound, again gave 2,3-epoxypropyl O-β- d-galactopyranosyl-(1→6)- O-β- d-galactopyranosyl-(1→6)- O-β- d-galactopyranosyl-(1→6)-β- d-galactopyranoside ( 19). Compounds 17 and 19 showed a high degree of affinity for antigalactan monoclonal antibodies IgA J539 and IgA X24.