1-Hydroxy-3-amino-2-piperidone (δ-N-Hydroxycycloornithine) Derivatives: Key Intermediates for the Synthesis of Hydroxamate-Based Siderophores

Article abstract of DOI:10.1021/jo00293a010

Several routes for the synthesis of δ-N-(benzyloxy)cycloornithine (2) from glutamic acid derived starting materials are described.Efficient methods were developed for the synthesis of glutamic acid γ-semialdehyde and γ-hydroxynorvaline derivatives as key substrates for the preparation of δ-N-hydroxyornithine analogues.Thus, the best approaches to the synthesis of 2 were: (1) reductive cyclization of an N-hydroxysuccinimide ester of the O-benzyloxime 4 of α-amino-protected glutamic acid γ-semialdehyde 5 and (2) cyclization of the N-(benzyloxy)amide of δ-bromonorvaline (7).