Studies on new dehydropeptidase inhibitors. II. Structural elucidation and synthesis of WS1358A1 and B1

The structures of WS1358A1 and B1, new dehydropeptidase inhibitors isolated from Streptomyces parvulus subsp. tochigiensis No. 1358, have been established to be 2-hydroxy-2-hydroxyaminocarbonyl-3-methylglutaric acid (1) and 2-hydroxy-2-hydroxyaminocarbonylglutaric acid (2), respectively, on the basis of spectroscopic evidence and synthesis of the racemates.