Title: Fialuridine
CAS Registry Number: 69123-98-4
CAS Name: 1-(2-Deoxy-2-fluoro-b-D-arabinofuranosyl)-5-iodo-2,4(1H,3H)-pyrimidinedione
Additional Names: 1-(2-deoxy-2-fluoro-b-D-arabinofuranosyl)-5-iodouracil; 5-iodo-2¢-fluoroarauracil; FIAU
Molecular Formula: C9H10FIN2O5
Molecular Weight: 372.09
Percent Composition: C 29.05%, H 2.71%, F 5.11%, I 34.11%, N 7.53%, O 21.50%
Literature References: Exptl antiviral agent; nucleoside analog with antihepatitis B activity. Prepn: K. A. Watanabe et al., J. Med. Chem. 22, 21 (1979). Antiviral activity: J. M. Colacino, C. Lopez, Antimicrob. Agents Chemother. 24, 505 (1983); K. A. Staschke et al., Antiviral Res. 23, 45 (1994). Clinical pharmacokinetics: R. R. Bowsher et al., Antimicrob. Agents Chemother. 38, 2134 (1994). Report of trial suspension: S. R. Ahmed, Lancet 342, 166 (1993). Evaluation of mechanism of hepatotoxicity: L. Cui et al., J. Clin. Invest. 95, 555 (1995). Clinical toxicological profile: W. Stevenson et al., Transplant. Proc. 27, 1219 (1995).
Properties: Crystals from ethanol, mp 216-217°.
Melting point: mp 216-217°
Fibrin Fibroblast Growth Factor Fibrolase Fibronectins Fichtelite

Skeletal formula
Ball-and-stick model
Systematic (IUPAC) name
1-[(2R,3S,4R,5R)-3-Fluoro-4-hydroxy-5-(hydroxymethyl)- 2-tetrahydrofuranyl]-5-iodopyrimidine-2,4-dione
Clinical data
Legal status  ?
ATC code None
PubChem CID 50313
KEGG D04181 YesY
NIAID ChemDB 070971
Synonyms 2′-Fluoro-5-iodouracil
Chemical data
Formula C9H10FIN2O5 
Mol. mass 372.09 g/mol
 N (what is this?)  (verify)

Fialuridine, or 1-(2-deoxy-2-fluoro-1-D-arabinofuranosyl)-5-iodouracil (FIAU), is a nucleoside analogue. It was originally designed as a therapy for hepatitis B virus infection. In a 1992 clinical study at the NIH, unexpected toxicity led to the death of 5 out of 15 patients from fulminant liver failure associated with lactic acidosis. This toxicity was unusual in that it was not predicted by animal studies. It is suspected that the drug induced mitochondrial damage, as hinted by in-vitro studies.