13C-n.m.r. studies of the acetylation sequences in partially N-deacetylated chitins (chitosans).
Chitosans obtained under homogeneous conditions of N-deacetylation, with degrees of N-deacetylation between 46% and 94%, were depolymerised and their 125-MHz 13C-n.m.r. spectra have been interpreted. The sequence of 2-acetamido-2-deoxy-beta-D-glucopyranose (GlcNAc) and 2-amino-2-deoxy-beta-D-glucopyranose (GlcN) residues influenced the chemical shifts, and the diad and triad frequencies have been calculated. Chitosans that were N-deacetylated under homogeneous and heterogeneous conditions gave values for the diad and triad frequencies that were consistent with a random arrangement of GlcN and GlcNAc residues.
Vårum
K M
KM
Norwegian Biopolymer Laboratory (NOBIPOL), University of Trondheim.
Anthonsen
M W
MW
Grasdalen
H
H
Smidsrød
O
O
D000107:Acetylation; D002240:Carbohydrate Sequence; D002686:Chitin / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure
D002686:Chitin; D048271:Chitosan