Pierre C. Wyss

Synthesis of heparin saccharides—V : Anomeric o-benzyl derivatives of l-idopyranosyluronic acid☆

Abstract Derivatives of the anomeric benzyl l -idopyranosides and l -idopyranosiduronates have been synthesized from d -glucose as models for conformation studies. The two key reactions in the synthesis are: (a) inversion of configuration at C(5) of the d -glucofuranose derivative 4 , and (b) catalytic oxidation of the l -idopyranosides 19 , and 22 to uronic acids.

An Allylic Rearrangement Arising from Reaction of Fluoride Ion and A 3-Chloro, 4,5-Unsaturated Uronate Derivative

Abstract Reaction of methyl [benzyl 2-[(benzyloxycarbonyl)-amino]-3-chloro-2,3,4-trideoxy-β-L-threo-hex-4-enopyrano-sid]uronate,3,4-trideoxy-β-L-threo-hex-4-enopyranosidjuronate (7) with silver fluoride gave the 5-fluoro, 3,4-unsaturated uronate derivative 8, which, on treatment with methanolic ammonia, afforded the corresponding 5-meth-oxy, uronamide 9. The structures of 8 and 9 were confirmed by spectral data and by x-ray crystallographic analysis of 8. 1H NMR spectroscopy parameters for 9 and its diastercomen 11 have been used to probe the conformational preferences in solution.