Isolation and Characterization of Sulfated Disaccharides from the Deamination Products of Porcine Heparin (α-Heparin) and Whale Heparin (ω-Heparin), and a Comparison of the Deamination Products1

Abstract

Porcine heparin (α-heparin) and whale heparin (ω-heparin) were deaminated, and sulfated disaccharides, compounds b-2, e-2-1, e-2-2, and e-2-3 from the former and compounds b′-2 and e′-2-l from the latter, were isolated from these products by high-voltage paper electrophoresis, gel filtration on Sephadex G-25 and column chromatography on Dowex 1x2 (Cl⁻ form) in succession. Based on the results of chemical, GLC and p.m.r. spectral analyses, together with previous observations, the structures of these sulfated disaccharides are proposed to be as follows: compounds b-2 and b′-2, 4-0-(cr-L-idopyranosyluronic acid 2-sulfate)-2,5-anhydro-D-mannose 6-sulfate; compounds e-2-1 and e′-2-l, 4-O-(a-L-idopyranosyluronic acid 2-sulfate)-2,5-anhydro-D-mannose; compound e-2-2, 4-0-{β-D-glucopyranosyluronic acid)-2,5-anhydro-D-mannose 6-sulfate; compound e-2-3, 4-0-{a-L-idopyranosyluronic acid)-2,5-anhydro-D-man-nose 6-sulfate. A high-voltage paper electrophoretogram of the deamination products of a-heparin was compared with a similar electrophoretogram of those of co-heparin. Except for fraction a from the former, both deamination products were composed of seven corresponding fractions, though they differed strikingly in their proportions. The proportion of higher oligosaccharides to disaccharides was smaller in the case of a-heparin than in that of co-heparin, reflecting the higher content of 2-acetamido-2-deoxy-D-glucose residues in the latter. The greatest difference was found in disaccharide fractions. The major fraction in a-heparin was disulfated disac-charide, compound b-2, whereas that in co-heparin was monosulfated disaccharide, compound e′-2-l. The present results indicate a lower content of 6-O-sulfated 2-amino-2-deoxy-D-glucose in co-heparin than in a-heparin. It is suggested therefore that a portion of 6-O-sulfates does not contribute significantly to the anticoagulant activity of heparin, since co-heparin has a higher activity than α-heparin.