biostudies-literatureFarrell REDepartment of Education, Australian GovernmentAustralian Institute of Nuclear Science and Engineering1973-1981https://www.ebi.ac.uk/biostudies/studies/S-EPMC11109934biostudies-literatureUnknown15(6)Phosphonate and phosphate prodrugs are integral to enhancing drug permeability, but the potential toxicity of their metabolites requires careful consideration. This study evaluates the impact of widely used phosphoramidate, bis-amidate, and cycloSal phosph(on)ate prodrug metabolites on BxPC3 pancreatic cancer cells, GL261-Luc glioblastoma cells, and primary cultured mouse astrocytes. 1-Naphthol and 2-naphthol demonstrated the greatest toxicity. Notably, 2-naphthol exhibited an ED₅₀ of 21 μM on BxPC3 cells, surpassing 1-naphthol with an ED₅₀ of 82 μM. Real-time xCELLigence experiments revealed notable activity for both metabolites at a low concentration of 16 μM. On primary cultured mouse astrocyte cells, all prodrugs exhibited reduced viability at 128 to 256 μM after RSC medicinal chemistryCytotoxicity of phosphoramidate, bis-amidate and cycloSal prodrug metabolites against tumour and normal cells.PMC11109934ALNSTU13115ALNSTU12886Farrell REMiddleton RJLiu GJSkropeta DSteele HfalseCytotoxicity of phosphoramidate, bis-amidate and cycloSal prodrug metabolites against tumour and normal cells.Phosphonate and phosphate prodrugs are integral to enhancing drug permeability, but the potential toxicity of their metabolites requires careful consideration. This study evaluates the impact of widely used phosphoramidate, bis-amidate, and cycloSal phosph(on)ate prodrug metabolites on BxPC3 pancreatic cancer cells, GL261-Luc glioblastoma cells, and primary cultured mouse astrocytes. 1-Naphthol and 2-naphthol demonstrated the greatest toxicity. Notably, 2-naphthol exhibited an ED₅₀ of 21 μM on BxPC3 cells, surpassing 1-naphthol with an ED₅₀ of 82 μM. Real-time xCELLigence experiments revealed notable activity for both metabolites at a low concentration of 16 μM. On primary cultured mouse astrocyte cells, all prodrugs exhibited reduced viability at 128 to 256 μM after 2024-01-01T00:00:00Z2024 Jun2026-06-05T09:54:55.824Z2025-08-18T09:52:59.232ZS-EPMC111099343890394510.1039/d4md00115j