Synthesis of Two D‐Glucosamine Derived 3,4‐Epoxides as Potential Scaffolds for Combinatorial Chemistry.

Abstract

Carbohydrates Carbohydrates U 0500Synthesis of Two D-Glucosamine Derived 3,4-Epoxides as Potential Scaffolds for Combinatorial Chemistry. -Two stereoisomeric D-glucosamine derived 3,4-epoxides (X) and (XIV), potential scaffolds for combinatorial chemistry applications, are synthesized in 5 and 6 steps, resp., from 2-acetamido-α-D-glucopyranoside (I). The stereochemical orientation of the epoxide is controlled through amino protecting group directed regioselective O-tosylation prior to epoxide formation. Moreover, preliminary studies on the opening of epoxide (XIV) in solution are described. -(SVEJGAARD, L.; FUGLSANG, H.; JENSEN, P. B.; KELLY, N. M.; PEDERSEN, H.; ANDERSEN, K.; RUHLAND, T.; JENSEN*, K. J.; J. Carbohydr. Chem. 22 (2003) 3-4, 179-184; Chem. Dep., R. Vet. Agric. Univ., DK-1871 Frederiksberg, Copenhagen, Den.; Eng.) -M. Kowall 38-176

Synthesis of a Glycosylphosphatidylinositol (GPI) Fragment as a Potential Substrate for Mannoprotein Transglycosidases

“…Although not widely using in complex carbohydrate synthesis, a direct approach to the cleavage of N-acetyl groups involves treatment with hydrazine hydrate at the reflux. 29 Because hydrazine hydrate had been previously used in the presence of methyl glycosides, it was tested here on the 2-acetamido glycosides 20 and 22 (Scheme 6). First, ester deprotection was achieved by treatment with NaOMe in MeOH, affording the deprotected 2-acetamido compounds 20 and 22 in yields of 90 and 96%, respectively.…”