Use of the aryl groups as the carboxyl synthon. Application to the synthesis of some natural products containing hydroxy amino acid functions

Abstract

The aryl groups are easily converted to the carboxyl group by oxidation with ruthenium tetroxide. Utilizing this transformation as a key step, several phytosiderophores (mugineic acid (1), 3-epi-hydroxymugineic acid (2), 2‣-hydroxynicotianamine (3), and distichonic acid A (4)) and polyoxamic acid (5), the side chain moiety of the antifungal antibiotics polyoxins, have been efficiently and stereoselectively synthesized. © 1994 IUPAC