Acylation of <i>N</i>δ-Benzyloxyornithine

Abstract

Abstract Acetylation of Nδ-benzyloxyornithine monohydrobromide (I·HBr) with acetic anhydride gave the Nδ-acetylated product, which yielded Nδ-acetyl-Nδ-hydroxyornithine by catalytic reduction. On the other hand, acetylation or alkoxycarbonylation of Nδ-benzyloxyornithine(I) proceeded through Nα-acetylation, followed by spontaneous cyclization to form lactams, which yielded cyclic hydroxamic acids on catalytic reduction. These hydroxamic acid and Nδ-acetyl-Nδ-hydroxyornithine were readily hydrolyzed to give Nδ-hydroxyornithine.