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Drug resistant uropathogenic E. coli associated with urinary tract infections (UTIs) are a serious and debilitating health threat. Therefore new drug targets to treat this disease need to be explored. One possible approach is to block the synthesis of the nucleoside monophosphates required for DNA/RNA production in these pathogens. In E. coli, the purine salvage pathway has two 6‐oxopurine phosphoribosyltransferases (PRTs), xanthine‐guanine PRT (EcXGPRT) and hypoxanthine PRT (EcHPRT). Here, we investigate acyclic nucleoside phosphonates (ANPs) as inhibitors of EcHPRT and have determined six crystal structures of EcHPRT in complex with ANPs. These data reveal the binding modes of these compounds and can assist in future rational structure‐based design efforts. It is suggested that a combination of inhibitors that block de novo and salvage pathways is a plausible approach to developing new antibiotics for E. coli UTIs. In addition, we provide details of a novel approach to accelerating the crystallization of this enzyme that may be of general applicability for rational drug discovery.

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A combination of NMR and IRPD spectroscopy confirmed the existence of predicted cyclic phosphorus intermediates involved in ProTide prodrugs activation.

The fluorine atom plays an important role in medicinal chemistry because fluorine substitution has a strong impact on the physical, chemical, and biological properties of bioactive compounds. Such fluorine modifications have also been extensively studied among the pharmaceutically important class of nucleoside phosphonates, nucleotide analogues in which the phosphate group is replaced by the enzymatically and chemically stable phosphonate moiety. The fluorinated nucleoside phosphonates abound with antiviral, antiparasitic, and anticancer properties because they are able to act as inhibitors of important enzymes of nucleoside/nucleotide metabolism. In this paper, we review the biological properties of cyclic and acyclic nucleoside phosphonates modified by the attachment of one or more fluorine atoms to various parts of the molecule, namely to nucleobases, alkylphosphonate groups, cyclic or acyclic linkers, or to prodrug moieties.

This paper deals with a novel, efficient and environmentally friendly synthesis of dialkyl haloalkylphosphonates via a microwave-assisted Michaelis-Arbuzov reaction. The approach is solventless, requires only one equivalent of each of the starting compounds, and provides high yields of pure products from which the impurities are easy to remove. The process has been optimised for batch and flow reactors and is especially profitable for the production of key intermediates in synthesis of Ethephon or acyclic nucleoside phosphonates such as adefovir, tenofovir, and cidofovir.

Acyclic nucleoside phosphonates (ANPs) are an important class of therapeutic drugs that act as antiviral agents by inhibiting viral DNA polymerases and reverse transcriptases. ANPs containing a 6-oxopurine unit instead of a 6-aminopurine or pyrimidine base are inhibitors of the purine salvage enzyme, hypoxanthine-guanine-[xanthine] phosphoribosyltransferase (HG[X]PRT). Such compounds, and their prodrugs, are able to arrest the growth of Plasmodium falciparum (Pf) in cell culture. A new series of ANPs were synthesized and tested as inhibitors of human HGPRT, PfHGXPRT, and Plasmodium vivax (Pv) HGPRT. The novelty of these compounds is that they contain a five-membered heterocycle (imidazoline, imidazole, or triazole) inserted between the acyclic linker(s) and the nucleobase, namely, 9-deazahypoxanthine. Five of the compounds were found to be micromolar inhibitors of PfHGXPRT and PvHGPRT, but no inhibition of human HGPRT was observed under the same assay conditions. This demonstrates selectivity of these types of compounds for the two parasitic enzymes compared to the human counterpart and confirms the importance of the chemical nature of the acyclic moiety in conferring affinity/selectivity for these three enzymes.