Anomeric spirohydantoins of mannofuranose : approaches to novel anomeric amino acids by an oxidative ring contraction

Abstract Bromine-induced oxidative ring contraction of an α-amino-δ-lactone gave a mixture of α-aminotetrahydrofurancarboxylic esters which may allow the preparation of stable amino acid derivatives at the anomeric position of mannofuranose. The synthesis of N -phenylhydantoins at the anomeric position of mannofuranose is reported.