Mutarotation

Ketose-phosphonates may adopt open chain, or a- or b-furanosyl, or a- or b-pyranosyl configurational
isomers in aqueous solution. An HPLC and NMR analysis of a series of ketose-phosphonates with a thymidylyltransferase (dTDP-glucose pyrophosphorylase) implied a rapid dynamic equilibrium between the pyranosyl forms of gluco-ketose phosphonate leading to efficient production of unique
sugar nucleotide analogues. The preparation of diastereomerically pure gluco-configured monofluoromethylenephosphonates enabled the determination of the thymidylyltransferase preference for CHF stereochemistry. The effects of acidity upon thymidylyltransferase substrate specificity were determined using a series of monofluoro- and difluoro- ketose-phosphonates. WaterLOGSY NMR
spectroscopy demonstrated a switching of the ordered Bi-Bi mechanism with ketose-phosphonate substrates. Ketose-phosphonates are presented as a unique class of sugar 1-phosphate analogues with potential applications as glycosyltransferase probes