Some chemical,enzymic, and physical properties of di-saccharides from beef-lung heparin

A study is reported of the reactivities of the disaccharides isolated after deamination of beef-lung heparin and reduction of the products by sodium borotritide: 2,5-anhydro-O-(α-l-idopyranosyluronic acid sulfate)-d-mannitol sulfate, SIMS; 2,5-anhydro-O-(α-l-idopyranosyluronic acid)-d-mannitol sulfate, IMS; 2,5-anhydro-O-(α-l-idopyranosyluronic acid sulfate)-d-mannitol, SIM; and 2,5-anhydro-O-(β-d-glucopyranosyluronic acid)-d-mannitol sulfate, GMS. Results for the non-sulfated disaccharides IM and GM, prepared by desulfation of SIMS and GMS, are also reported. SIMS and SIM were inert to purified α-l-iduronidase, showed unexpected resistance to periodate oxidation, and lost sulfate rapidly in 50mm hydrochloric acid at 100°. Hydrolysis of IM and of IMS was catalyzed by α-l-iduronidase, and of GM and GMS by β-d-glucuronidase; the radioactive products were identified as 2,5-anhydro-d-mannitol (aM) and its sulfate (aMS). The products SIM and IMS obtained by deamination of heparin and desulfation of SIMS (the major deamination product) are apparently identical. In heparin partially desulfated by methanolic hydrogen chloride, residual sulfate groups were mostly linked to l-iduronic acid residues. Chemical, chromatographic, and electrophoretic methods that are valuable for separation and characterization of the disaccharides are described.