N-ACETYL-beta-D-GLUCOSAMINE (1398-61-4) Physical and Chemical Properties
N-ACETYL-beta-D-GLUCOSAMINE
A monosaccharide amino sugar (GlcNAc) used as a biochemical building block and analytical standard for glycobiology, synthesis and QC workflows.
| CAS Number | 1398-61-4 |
| Family | Amino sugars (HexNAc) |
| Typical Form | White amorphous solid (powder) |
| Common Grades | EP, USP |
N-Acetyl-beta-D-glucosamine (commonly abbreviated GlcNAc or NAG) is an N-acetylated hexosamine and a monosaccharide derivative of D-glucose in the pyranose form. Structurally it is a 2-acetamido-2-deoxy-beta-D-glucopyranose: a six-membered oxane (pyranose) ring bearing multiple secondary alcohols, a primary hydroxymethyl group at C6, and an N-acetyl amide substituent at C2. The molecule contains five defined stereocenters and exists primarily as a beta anomer in many biological contexts; when polymerized via beta-(1→4) linkages it forms chitin, a major structural polysaccharide in many organisms.
Electronically, the N-acetyl moiety confers an amide functionality that is less basic than a free amino sugar (glucosamine), while the array of hydroxyl groups and the acetamide oxygen provide multiple hydrogen-bond donors and acceptors. The computed descriptors indicate a high polar surface area and multiple H-bonding sites, consistent with strong aqueous-phase interactions and low intrinsic lipophilicity. The neutral formal charge at physiological pH, combined with high polarity and a calculated XLogP of -1.7, predicts a molecule that partitions poorly into nonpolar media and interacts strongly with water and polar proteins.
Chemically and biologically, the compound is chemically stable under mild neutral conditions but is susceptible to enzymatic cleavage (e.g., glycosidases and deacetylases) and acid-catalyzed hydrolysis of glycosidic bonds when incorporated into oligo- or polysaccharides. It is widely relevant industrially and biologically as the monosaccharide building block of chitin and as the O-GlcNAc modification unit in intracellular and secreted proteins; GlcNAc residues participate in structural biopolymers and in reversible post-translational modification that modulates signaling and protein function. Common commercial grades reported for this substance include: EP, USP.
Molecular Overview
Molecular Weight and Composition
- Molecular formula: C8H15NO6
- Molecular weight: 221.21 \(\mathrm{g}\,\mathrm{mol}^{-1}\)
- Exact mass / Monoisotopic mass: 221.08993720 Da
- Heavy atom count: 15
- Defined atom stereocenter count: 5
- Structural identifiers (plain text):
- SMILES: CC(=O)N[C@@H]1C@HO
- InChIKey: OVRNDRQMDRJTHS-FMDGEEDCSA-N
The molecule is a single covalently bonded unit with low rotatability (rotatable bond count = 2) relative to its number of hydroxyl substituents; that constrained conformational flexibility is typical of hexopyranoses and influences crystal packing and specific protein recognition. Topological and stereochemical complexity (complexity = 235) reflects the multiple chiral centers and substitution pattern typical for biologically active saccharide derivatives.
Selected experimental ion-mobility collision cross sections (reported for different adduct and instrument calibrations) include values such as 150.7 \(\text{Å}^2\), 152.09 \(\text{Å}^2\), 153 \(\text{Å}^2\) and 146.31 \(\text{Å}^2\) for various [M+Na]+, [M+H]+ and [M-H]- species; these are consistent with a compact, highly hydrated monosaccharide conformation in the gas phase.
Charge, Polarity, and LogP
- Formal charge: 0
- XLogP3: -1.7
- Topological polar surface area (TPSA): 119 (\(\text{Å}^2\))
- Hydrogen bond donors: 5
- Hydrogen bond acceptors: 6
The neutral formal charge and negative XLogP indicate low lipophilicity; combined with TPSA = 119 \(\text{Å}^2\) and multiple H‑bond donors/acceptors, the molecule is highly polar and expected to be strongly solvated in polar solvents. These descriptors are consistent with limited partitioning into hydrophobic phases and favorable interaction with aqueous environments and polar binding sites on proteins.
Biochemical Classification
N-Acetyl-beta-D-glucosamine is classed as a HexNAc monosaccharide derivative and functions both as a glycan monomer (building block of beta-(1→4)-linked chitin) and as the O-GlcNAc motif when enzymatically attached to serine/threonine residues in proteins. It is a common component in glycoconjugates and is broadly classified under aminoglycans / N-acylglucosamines.
Chemical Behavior
Stability and Degradation
As a standalone monosaccharide derivative, the acetamido sugar is chemically stable under neutral aqueous conditions. The N-acetyl amide and glycosidic linkages (when present in oligo- or polysaccharides) can be cleaved under strongly acidic conditions (acid-catalyzed hydrolysis) or by hydrolytic enzymes. Oxidation of the primary C6 hydroxymethyl unit to an aldehyde or carboxylate requires strong oxidants or enzymatic catalysts; such oxidative transformations are not spontaneous under typical storage conditions. Thermal decomposition and Maillard-type reactions can occur under elevated temperature and reactive carbonyl conditions but are not relevant for routine low-temperature storage of the pure monosaccharide.
Enzymatic pathways (see below) provide the principal routes for degradation and interconversion in biological systems; enzymatic specificity and the biochemical milieu therefore dominate in vivo stability and turnover.
Hydrolysis and Transformations
- Enzymatic deacetylation: Deacetylases (e.g., chitin deacetylases) convert N-acetylglucosamine residues to glucosamine (2-amino-2-deoxy-D-glucose) under biological conditions.
- Enzymatic cleavage of glycosidic bonds: Exo- and endo- glycosidases (e.g., N-acetylglucosaminidases) hydrolyze beta-(1→4) linkages in oligo- and polysaccharides containing GlcNAc, releasing monomeric NAG.
- Polymerization and depolymerization: Biosynthetic polymerization via beta-(1→4) glycosidic bonds produces chitin; chemical depolymerization typically requires acid hydrolysis or specific enzymatic cocktails.
These transformation pathways reflect the dual roles of GlcNAc as both a monomeric metabolite and a constituent of higher-order glycans; chemical hydrolysis pathways are generally more aggressive than enzymatic routes and are used analytically to depolymerize chitinous materials.
Biological Role
Functional Role and Pathways
N-Acetyl-beta-D-glucosamine plays two broad biological roles: (1) as the monomeric unit of chitin, forming structural polymers in fungi, arthropods and some algae; and (2) as the monosaccharide used in protein O-GlcNAcylation, a reversible post-translational modification affecting cytoplasmic and nuclear proteins. O-GlcNAc modification is catalyzed by transferases that append the GlcNAc residue to Ser/Thr side chains and by specific glycosidases that remove it, establishing a dynamic regulatory modification that can compete with or complement phosphorylation in cell signaling pathways.
The molecule is also an intermediate/metabolite in amino sugar metabolism and participates in pathways that generate nucleotide-sugar donors (e.g., UDP-GlcNAc), which are substrates for glycosyltransferases that assemble complex glycans and glycoconjugates.
Physiological and Cellular Context
- Reported cellular location: cytoplasm (noting that O-GlcNAc-modified proteins can be cytoplasmic, nuclear, or associated with other compartments depending on the protein).
- Occurrence: present across diverse taxa (including Homo sapiens, Mus musculus, Saccharomyces cerevisiae, Drosophila melanogaster and many bacteria and viruses in glycan contexts).
- Structural role: as polymeric chitin in exoskeletons and cell walls; as monomeric or short-oligomeric GlcNAc in glycan remodeling and signaling.
- Clinical development: N-acetylglucosamine has been investigated in clinical settings (maximum reported trial phase II for an investigational indication); specifics of indications are not provided here.
Because GlcNAc participates in fundamental glycosylation and structural pathways, it is widely studied in enzymology, glycobiology, and materials science (e.g., chitin-derived materials).
Identifiers and Synonyms
Registry Numbers and Codes
- CAS Registry Number: 1398-61-4
- EC (European Community) Number: 215-744-3
- UNII: 8P59336F68
- ChEBI: CHEBI:17029
- ChEMBL: CHEMBL447878
- DrugBank: DB15142
- KEGG: C03878
- InChIKey: OVRNDRQMDRJTHS-FMDGEEDCSA-N
- SMILES: CC(=O)N[C@@H]1C@HO
- GlyTouCan accession: G49108TO
- PDBe ligand code (common): NAG
These identifiers are commonly used for procurement, database cross-referencing, and spectral annotation in analytical workflows.
Synonyms and Biological Names
Representative synonyms and names reported for this compound include:
N-Acetyl-beta-D-glucosamine; 2-acetamido-2-deoxy-beta-D-glucopyranose; GlcNAc; NAcGlc; Beta-N-Acetylglucosamine; 2-Acetamido-2-deoxy-beta-D-glucose; b-GlcNAc; N-acetyl-D-glucosamine (complete stereochemistry).
(Additional vendor and depositor synonyms may exist; select canonical identifiers above for unambiguous procurement and quality control.)
Safety and Handling Overview
Handling and Storage of Biochemical Materials
N-Acetyl-beta-D-glucosamine is generally handled as a hygroscopic, highly polar crystalline or amorphous solid that should be stored in a tightly sealed container under dry conditions and protected from prolonged exposure to high temperature to minimize degradation and Maillard-type reactions. Standard precautions for solid biochemical materials apply: minimize dust generation, use appropriate local exhaust or dust collection, and employ suitable personal protective equipment (lab coat, gloves, eye protection). For laboratory manipulations, use engineering controls and procedures to avoid inhalation and contact with mucous membranes.
Available hazard summaries indicate that preparations of chitin/chitosan materials are not typically classified as hazardous by conventional global harmonized criteria and that irritation is the principal reported effect in some cases; however, specific formulations and impurities can alter hazard profiles. For accidental release and disposal, prioritize recovery and recycling of usable material where appropriate and follow institutional and local regulations for disposal of biological/chemical solids.
For detailed hazard, transport and regulatory information, users should refer to the product-specific Safety Data Sheet (SDS) and local legislation.
