The Synthesis and Enzymatic Evaluation of Biologically Relevant Sugar 1-Phosphonates

Abstract

Phosphonates are commonly used as hydrolytically stable phosphate mimics to explore a multitude of biological processes. This general approach has lead to the development of enzyme inhibitors, antifungals, antibiotics, and anticancer agents. Physiologically, sugar 1-phosphates are utilized by nucleotidylyltransferases which catalyze the condensation of sugar 1-phosphates with nucleotides to generate sugar nucleotides. These enzymes can be exploited to generate novel sugar nucleotides, including phosphonate analogues of sugar 1-phosphates. Inhibiting these enzymes with phosphonate analogues may also lead to novel therapeutic opportunities. To explore these enzymes there is a need to generate novel sugar 1-phosphate analogues; however, access to these analogues is limited by the lack of synthetic methodologies. A library of galacto-configured ketose phosphonates was synthesized, generating analogues that included mono and difluorination at the methylene functionality alpha to the phosphorus. Methods were explored to generate gluco-configured alpha hydroxy phosphonates. The interactis of these compounds with a series of enzymes were studied, including the thymidylyltransferase Cps2L and the uridylyltransferases GalT and AtUSP. Studies included investigating the substrate specificity of these enzymes, as well as enzyme-ligand binding experiments using WaterLOGSY NMR spectroscopy. In addition, the synthesis of prodrug analogues of the galacto-configured ketose phosphonates were also explored.