Syntheses and studies of multiwarhead siderophore-5-fluorouridine conjugates
摘要:
Siderophores are microbial iron chelating agents that: sequester physiologically essential iron for microbes. Conjugation of drugs to siderophores allows use of active iron transport for microbially directed drug delivery. Syntheses and biological studies are described of the first multidrug isocyanurate-based siderophore analogues separately containing one, two, and three 5-fluorouridine (5-FU) derivatives as the drug component. The results indicate that a single siderophore can be used to deliver multiple drugs to target pathogenic microorganisms. (C) 1999 Elsevier Science Ltd. All rights reserved.
5'-O-Acyl-5-fluorouridines and 5'-O-acyl-5-sluorocytidines are prepared by the direct acylation of the 5'-hydroxyl group with amino acids under Mitsunobu conditions and the amino acyl derivatives are coupled with other amino acids or peptides to provide antibacterial and antifungal derivatives of the nucleosides. For example, 5-fluorouridine is acylated at the 5'-hydroxyl group with an amino protected L-valine and the acylation product is deprotected to provide 5'-O-(L-valinyl)-5-fluorouridine having activity against Gram-positive bacteria including resistant staphylococcus. Preferred peptide derivatives comprise the tripeptides of ornithine and lysine wherein the terminal amino group is substituted by both hydroxy and acetyl. The latter peptides inhibit the growth of C. albicans.