Abstract
The structures of the antibiotics FR-900098 (II) and FR-33289 (III), isolated from Streptomyces rubellomurius, have been established as 3-(N-acetyl-N-hydroxyamino)-propylphosphonic acid and 3-(N-acetyl-N-hydroxyamino)-2 (R)-hydroxypropylphosphonic acid, respectively, on the basis of spectroscopic and chemical evidence and, finally, by synthesis.