Title: Adefovir
CAS Registry Number: 106941-25-7
CAS Name: [[2-(6-Amino-9H-purin-9-yl)ethoxy]methyl]phosphonic acid
Additional Names: 9-(2-phosphonylmethoxyethyl)adenine; PMEA
Manufacturers' Codes: GS-393
Molecular Formula: C8H12N5O4P
Molecular Weight: 273.19
Percent Composition: C 35.17%, H 4.43%, N 25.64%, O 23.43%, P 11.34%
Literature References: Acyclic nucleoside phosphonate (ANP) analog. Prepn: A. Holy, I. Rosenberg, EP 206459; eidem, US 4808716 (1986, 1989 both to Ceskoslov. Akad. Ved); eidem, Collect. Czech. Chem. Commun. 52, 2801 (1987); of dipivoxil ester prodrug: J. E. Starrett, Jr. et al., EP 481214 (1992 to Bristol-Myers Squibb); eidem, US 5663159 (1997 to Inst. Org. Chem. Biochem. Acad. Sci. Czech Rep.; Rega). Crystal structure: C. H. Schwalbe et al., J. Chem. Soc. Perkin Trans. 1 1991, 1348. HPLC determn: P. Augustijns et al., J. Liq. Chromatogr. Relat. Technol. 19, 2271 (1996). Clinical pharmacokinetics: K. C. Cundy et al., Antimicrob. Agents Chemother. 39, 2401 (1995). Review of pharmacology and therapeutic potential: L. Naesens et al., Antiviral Chem. Chemother. 8, 1-23 (1997). Clinical trial in HIV infected patients: J. Kahn et al., J. Am. Med. Assoc. 282, 2305 (1999); in hepatitis B virus (HBV): R. J. C. Gilson et al, J. Viral Hepat. 6, 387 (1999). Resistance surveillance in HBV infections: H. Yang et al., Hepatology 36, 464 (2002).
Properties: Off-white crystalline solid, mp >250°. pKa1 2.0, pKa2 6.8. uv max (H2O) 208, 260 nm (e 19600, 14100); (0.1N HCl) 210, 260 nm (e 19000, 13700); (0.1N NaOH) 216, 262 nm (e 9600, 14500).
Melting point: mp >250°
pKa: pKa1 2.0, pKa2 6.8
Absorption maximum: uv max (H2O) 208, 260 nm (e 19600, 14100); (0.1N HCl) 210, 260 nm (e 19000, 13700); (0.1N NaOH) 216, 262 nm (e 9600, 14500)
Derivative Type: Di(pivaloyloxymethyl) ester
CAS Registry Number: 142340-99-6
Additional Names: Adefovir dipivoxil; bis(POM)-PMEA
Manufacturers' Codes: GS-840
Trademarks: Hepsera (Gilead); Preveon (Gilead)
Molecular Formula: C20H32N5O8P
Molecular Weight: 501.47
Percent Composition: C 47.90%, H 6.43%, N 13.97%, O 25.52%, P 6.18%
Properties: Off-white crystalline powder. Soly in water (mg/ml): 19 (pH 2.0); 0.4 (pH 7.2). Log P (octanol/aq phosphate buffer): 1.91.
Log P: Log P (octanol/aq phosphate buffer): 1.91
Therap-Cat: Antiviral.
Keywords: Antiviral; Purines/Pyrimidinones.
A-Denopterin Adenosine Adenosine Diphosphate Adhatoda Adinazolam

Systematic (IUPAC) name
{[2-(6-amino-9H-purin-9-yl)ethoxy]methyl}phosphonic acid
Clinical data
AHFS/ monograph
Pregnancy cat. C (US)
Legal status Prescription only
Routes Oral
Pharmacokinetic data
Bioavailability 59%
Half-life 7.5 hours
CAS number 106941-25-7 N
ATC code J05AF08
PubChem CID 60172
DrugBank DB00718
ChemSpider 54252 YesY
UNII 6GQP90I798 YesY
KEGG D02768 YesY
NIAID ChemDB 028595
Chemical data
Formula C8H12N5O4P 
Mol. mass 273.186 g/mol
 N (what is this?)  (verify)

Adefovir is a prescription medicine used to treat (chronic) infections with hepatitis B virus. Adefovir was previously called bis-POM PMEA, with trade names Preveon and Hepsera. It is an orally-administered nucleotide analog reverse transcriptase inhibitor (ntRTI). It can be formulated as the pivoxil prodrug adefovir dipivoxil.