Pergamon Bioorganic & Medicinal Chemistry Letters 9 (1999) 2941-2946 BIOORGANIC & MEDICINAL CHEMISTRY LETTERS AN EFFICIENT SYNTHESIS OF TWO MONOSULFATED TRISACCHARIDES WITH THE Gall31,3GlcNAcl31,3Gall3-O-Allyl BACKBONE Jie Xia, Conrad F. Piskorz, Robert D. Locke, E. V. Chandrasekaran, James L. Alderfer, and Khushi L. Matta * Department of Molecular & Cellular Biophysics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, U.S.A. Received 26 July 1999; accepted 7 September 1999 Abstract: The GlcNAcl3(1-~3) Gal linked disaccharide 7 was synthesized as key building blocks for the construction of target monosulfated trisaccharides 1 and 2 using oxazoline 3 as glycosyl donor promoted by BF3.EhO © 1999ElsevierScienceLtd. All rights reserved. Localization of sulfate groups to defined positions in glycoproteins suggests a physiological role for these groups. The major structural motif of mucins synthesized by a highly metastatic colon carcinoma cell line has been identified as a sulfated Lewis x determinant) Mucin from a non-secretor, chronic bronchitis patient contained sulfated oligosaccharides of core 1, 2 or 4 structures, while that from secretor individuals with cystic fibrosis involved core 2 structures only.z' 3 Such differences in the localization of sulfate in mucin oligosaccharide chains may have clinical relevance. We reported earlier that human colon Gal: 3-0- sulfotransferase can utilize only the type 1 sulfated disaccharide compound, Gal[31,3(6-O-sulfo)GlcNAcl3- O-Allyl as an acceptor. 4 Interestingly, sulfated oligosaccharide with the 3-0- sulfoGal[31,3GlcNAc131,3Gal131,3GalNAcct- structure was identified in chronic bronchitis mucin.-' We here describe the synthesis of Y'-O-sulfo and 6'-O-sulfo derivatives of GalI31,3GIcNAcl31,3Gall3-O-Allyl for specificity studies of glycosyltransferases and sulfotransferases. Further preparation of acrylamide copolymers may potentially provide inhibitors of selectin binding. Chemistry Synthesis of two monosulfated trisaccharides (3SO3Na)Gal (I31--->3)GIcNAc[3(1---~3)Gall3-O Allyl 1 and Gall3 (1-->3)(6SO3Na)GIcNAcl3 (1-+3)Gal[3-O Allyl 2: The synthesis of these two compounds involved the use of the key intermediates: 2-methyl (3,4,6-tri-O-acetyl-l,2-dideoxy-c~-d-glucopyrano) [2,1- d]-2-oxazoline 3, allyl 6-O-trimethylacetyl-[3-d-galactopyranosyl bromide 5. The original oxazoline 0960-894X/99/$ - see front matter © 1999 Elsevier Science Ltd. All rights reserved. PII: S0960-894X(99)00507-7