Fosmidomycin (1a) and FR-90098 are potent inhibitors of 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR), the second enzyme of the non-mevalonate (MEP) pathway responsible for the biosynthesis of isoprenoids. This paper describes the synthesis of four types of targets bearing a phosphanyl-phosphonicacid motif as the common core for the inhibition of DXR. In these structures, the hydroxamic acid