188003-27-2Relevant academic research and scientific papers
Conformational study of synthetic Δ4-uronate monosaccharides and glycosaminoglycan-derived disaccharides
Bazin, Helene G.,Capila, Ishan,Linhardt, Robert J.
, p. 135 - 144 (2007/10/03)
Sixteen Δ4-uronate monosaccharides were chemically synthesized. Their carboxy group was protected as a methyl or benzyl ester, the anomeric hydroxyl group as a benzyl glycoside and the 2 and 3 hydroxyl groups were protected with different substitution patterns as both ester and ether derivatives. Disaccharides containing Δ4-uronates were prepared from heparin using heparin lyases. Their carboxy group was unprotected or protected as a benzyl ester and the two hydroxyls in the uronate moiety were free, as O-sulfo derivatives or acylated. The conformation of these unsaturated uronate monosaccharide and disaccharide residues was studied using 1H NMR by examining interproton vic inal coupling constants. The Δ4-uronate residue adopted either the 2H1 or the 1H2 conformations. The equilibrium between these two conformers was shown to be controlled by substitution pattern.
Regio and stereoselective conversion of Δ4-uronic acids to L-ido- and D-glucopyranosiduronic acids
Bazin, Helene G.,Kerns, Robert J.,Linhardt, Robert J.
, p. 923 - 926 (2007/10/03)
Synthesis of L-ido- and D-glucopyranosiduronic acids was performed starting from protected Δ4-uronic acids 3a-f. Bromination of the C-4,5 double bond provided the trans-diaxial bromohydrin derivatives 6a-d, which were converted to the corresponding epoxides 7a-d in high yields. Direct reduction of these epoxides using borane-tetrahydrofuran complex afforded the D-glucopyranosiduronic acids 9b-d, while Lewis acid rearrangement through the C-4 keto intermediate 10b-d afforded the L-idopyranosiduronic acids 11b-d.
