N-Acetyl-D-galactosamine,?N-acetyl D-galactosamine (GalNAc) is an aldohexose (2-Acetamido-2-deoxygalactose) in which the hydroxyl group at position 2 is replaced by a N-Acetyl group (Collins, 2006). N-acetyl D-galactosamine forms a key part of both N- and O-linked glycoproteins, glycolipids, gangliosides, blood groups, glycosaminoglycans (chondroitin and dermatan sulfate) and human milk oligosaccharides. The number of GalNAc residues attached to the IgA O-linked glycans of Crohns Disease patients was significantly decreased, and strongly correlated with clinical activity. It is suggested that alterations of GalNAc attachment in IgA may be useful as a novel diagnostic and prognostic marker of Crohns Disease (Inoue, 2012).N-acetyl-D-Galactosamine (GalNAc) is an amino sugar derivative of galactose and a component of O-GalNAc glycans. It is transferred from UDP-GalNAc to the hydroxy group of protein serine or threonine residues by polypeptide GalNAc transferase, forming the Tn antigen, during the first step of mucin-type O-glycosylation. GalNAc has been used as a targeting moiety for liver-targeted delivery of oligonucleotides.CAS Number1811-31-0Product NameN-((2R,3R,4R,5R)-3,4,5,6-Tetrahydroxy-1-oxohexan-2-yl)acetamideIUPAC NameN-[(2R,3R,4R,5R)-3,4,5,6-tetrahydroxy-1-oxohexan-2-yl]acetamideMolecular FormulaC8H15NO6Molecular Weight221.21 g/molInChIInChI=1S/C8H15NO6/c1-4(12)9-5(2-10)7(14)8(15)6(13)3-11/h2,5-8,11,13-15H,3H2,1H3,(H,9,12)/t5-,6+,7+,8-/m0/s1InChI KeyMBLBDJOUHNCFQT-OSMVPFSASA-NSMILESCC(=O)NC(C=O)C(C(C(CO)O)O)OSynonymspoly-N-acetylgalactosamineCanonical SMILESCC(=O)NC(C=O)C(C(C(CO)O)O)OIsomeric SMILESCC(=O)N[C@@H](C=O)[C@H]([C@H]([C@@H](CO)O)O)O