ABSTRACT
The application of phosphorodiamidate technology to pyrimidine and purine nucleosides with anticancer activity to potentially overcome the resistance mechanisms associated with parent nucleosides is reported. Sixteen symmetrical phosphorodiamidates were prepared from the natural amino acids l-alanine and glycine. All the compounds were evaluated for their cytotoxic activity against a wide panel of solid and leukaemic tumour cell lines. In addition, a carboxypeptidase Y assay was performed on a representative phosphorodiamidate in order to reveal the putative bioactivation pathway for the reported phosphorodiamidate-type prodrugs.
Subject(s)
Antineoplastic Agents/pharmacology , Organophosphorus Compounds/pharmacology , Prodrugs/pharmacology , Purine Nucleosides/pharmacology , Pyrimidine Nucleosides/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cathepsin A/chemistry , Cell Line, Tumor , Enzyme Assays , Humans , Mice , Molecular Structure , Organophosphorus Compounds/chemical synthesis , Organophosphorus Compounds/chemistry , Prodrugs/chemical synthesis , Prodrugs/chemistry , Purine Nucleosides/chemical synthesis , Purine Nucleosides/chemistry , Pyrimidine Nucleosides/chemical synthesis , Pyrimidine Nucleosides/chemistryABSTRACT
The flavin-dependent thymidylate synthase X (ThyX), rare in eukaryotes and completely absent in humans, is crucial in the metabolism of thymidine (a DNA precursor) in many microorganisms including several human pathogens. Conserved in mycobacteria, including Mycobacterium leprae, and Mycobacterium tuberculosis, it represents a prospective anti-mycobacterial therapeutic target. In a M. tuberculosis ThyX-enzyme inhibition assay, N-(3-(5-(2'-deoxyuridine-5'-phosphate))prop-2-ynyl)octanamide was reported to be the most potent and selective 5-substituted 2'-deoxyuridine monophosphate analogue. In this study, we masked the two charges at the phosphate moiety of this compound using our ProTide technology in order to increase its lipophilicity and then allow permeation through the complex mycobacterial cell wall. A series of N-(3-(5-(2'-deoxyuridine))prop-2-ynyl)octanamide phosphoroamidates were chemically synthesized and their biological activity as potential anti-tuberculars was evaluated. In addition to mycobacteria, several DNA viruses depend on ThyX for their DNA biosynthesis, thus these prodrugs were also screened for their antiviral properties.
Subject(s)
Amides/chemistry , Antitubercular Agents/chemistry , Antiviral Agents/chemistry , Deoxyuridine/chemistry , Antitubercular Agents/chemical synthesis , Antitubercular Agents/pharmacology , Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/metabolism , Cell Line , Herpesvirus 3, Human/drug effects , Herpesvirus 3, Human/enzymology , Humans , Microbial Sensitivity Tests , Mycobacterium bovis/drug effects , Mycobacterium bovis/enzymology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/enzymology , Simplexvirus/drug effects , Simplexvirus/enzymology , Thymidylate Synthase/antagonists & inhibitors , Thymidylate Synthase/metabolismABSTRACT
The fluorinated pyrimidine family of nucleosides continues to represent major current chemotherapeutic agents for treating solid tumors. We herein report their phosphate prodrugs, ProTides, as promising new derivatives, which partially bypass the dependence of the current drugs on active transport and nucleoside kinase-mediated activation. They are also resistant to metabolic deactivation by phosphorolytic enzymes. We report 39 ProTides of the fluorinated pyrimidine FUDR with variation in the aryl, ester, and amino acid regions. Notably, only certain ProTide motifs are successful in delivering the nucleoside monophosphate into intact cells. We also find that the ProTides retain activity in mycoplasma infected cells, unlike FUDR. Data suggest these compounds to be worthy of further progression.
