Figure 1

Analysis of the pharmaceutical preparations of bovine (in blue) and porcine (in red) heparin by 1D ¹H NMR spectroscopy at 800 MHz. The signals designated as A1 correspond to H1 of N,6-disulfated α-glucosamine units; B1 and C1 to H1 of N-acetylated and 6-desulfated α-glucosamine units, respectively. These chemical modifications of the α-glucosamine units shift ~0.2 ppm downfield H1 of the neighbor 2-sulfated α-iduronic acid (I1 in the panel). Furthermore, 6-desulfation but not N-acetylation of the α-glucosamine units shift ~0.2 ppm downfield H5 of the same α-iduronic acid units (I5 in the panel). GlcN S-GlcA corresponds to H1 of N-sulfated α-glucosamine linked to β-glucuronic acid and GlcNS3S6S to H1 of N,3,6-trisulfated α-glucosamine units. I1 (deS)-A and I1(deS)-C are H1 of desulfated α-iduronic acid residues linked to N,6-disulfated and N-sulfated α-glucosamine units, respectively.