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Foscarnet

Also known as Phosphonoformic acid, Phosphonoformate, Carboxyphosphonic acid

Foscarnet chemical structure, CH3O5P, CAS 4428-95-9
2D chemical structure

Key facts

What buyers check first

CAS number
4428-95-9
Formula
CH3O5P
Molar mass
126.00 g/mol
EC number
112-287-0
HS code
293149
Category
Antibiotics and anti-infectives

What is Foscarnet?

Plain description, key identifiers and synonyms

Phosphonoformic acid is phosphoric acid in which one of the hydroxy groups is replaced by a carboxylic acid group. It is used as the trisodium salt as an antiviral agent in the treatment of cytomegalovirus retinitis (CMV retinitis, an inflamation of the retina that can lead to blindness) and as an alternative to ganciclovir for AIDS patients who require concurrent antiretroviral therapy but are unable to tolerate ganciclovir due to haematological toxicity. It has a role as a geroprotector, an antiviral drug, a HIV-1 reverse transcriptase inhibitor and a sodium-dependent Pi-transporter inhibitor. It is a member of phosphonic acids, a carboxylic acid and a one-carbon compound. It is functionally related to a formic acid and a phosphonic acid. It is a conjugate acid of a phosphonatoformate and a phosphonoformate(2-).

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
phosphonoformic acid
CAS number
4428-95-9 CAS number cross-checkedOther or deprecated CAS: 63585-09-1
EC number
112-287-0
Molecular formula
CH3O5P
UNII
364P9RVW4X
InChIKey
ZJAOAACCNHFJAH-UHFFFAOYSA-N
InChI
InChI=1S/CH3O5P/c2-1(3)7(4,5)6/h(H,2,3)(H2,4,5,6)
SMILES (canonical and isomeric)
C(=O)(O)P(=O)(O)O

Synonyms

  • Phosphonoformic acid
  • Phosphonoformate
  • Carboxyphosphonic acid
  • phosphonocarboxylic acid
  • Foscarmet
  • phosphonomethanoic acid
  • Phosphinecarboxylic acid, dihydroxy-, oxide
  • Dihydroxyphosphinecarboxylic acid oxide
  • dihydroxyphosphanecarboxylic acid oxide
  • Phgosphonocarboxylic acid
  • Formic acid, phosphono-
  • Forscarnet
  • 1nki
  • Foscarnet (PFA)
  • Phosphinecarboxylic acid, 1,1-dihydroxy-, 1-oxide, sodium salt (1:3)
  • PFA & rIFNalphaA
  • phosphonoformic acid(PFA)
  • MSL & PFA
  • Phosphono-formic acid(PFA)
  • hydroxycarbonylphosphonic acid
  • Foscarnet & IFN-alpha
  • DivK1c_000915
  • Foscarnet, Phosphonoformic Acid
  • Phosphonoformic acid & IFN-alpha
  • (PFA)dihydroxyphosphinecarboxylic acid oxide
Show all 29 synonyms
  • dihydroxyphosphinecarboxylic acid oxide(PFA)
  • Dihydroxy(oxo)-lambda~5~-phosphanecarboxylic acid
  • Phosphonoformate(trisodium) & Recombinant Alpha-A Interferon
  • Dihydroxyphosphinecarboxylic acid oxide and MSL, neutralizing monoclonal antibody

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

No measured properties are recorded for this substance yet. Ask suppliers for a technical data sheet.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
126.00 g/molcalc.
Exact mass
125.9718 Dacalc.
LogP (octanol/water)
-0.16calc.
Topological polar surface area
94.83 Ųcalc.
Hydrogen bond donors
3calc.
Hydrogen bond acceptors
2calc.
Rotatable bonds
1calc.
Heavy atoms
7calc.
Rings
0calc.
Aromatic rings
0calc.
Fraction sp3 carbons
0calc.
Formal charge
0calc.
Stereocentres
0calc.
Lipinski rule of five
Passes (0 violations)calc.

Calculated for screening. Confirm critical figures with the supplier.

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Warning
GHS08: Serious health hazard
Serious health hazard

Hazard statements

  • H341Suspected of causing genetic defects.
  • H373May cause damage to organs through prolonged or repeated exposure.
Precautionary statements (7)
  • P203Obtain, read and follow all safety instructions before use.
  • P260Do not breathe dust, fume, gas, mist, vapours or spray.
  • P280Wear protective gloves, protective clothing, eye protection and face protection.
  • P318If exposed or concerned, get medical advice.
  • P319Get medical help if you feel unwell.
  • P405Store locked up.
  • P501Dispose of contents and container in accordance with local regulations.

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Foscarnet suppliers

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  • China, ShanghaiUnclaimed profile
    FoscarnetGrade, purity and minimum order on request
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  • United States, San DiegoUnclaimed profile
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  • United States, San DiegoUnclaimed profile
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  • Germany, LorrachUnclaimed profile
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  • United States, HolbrookUnclaimed profile
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  • China, NanjingUnclaimed profile
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  • United States, AustinUnclaimed profile
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  • United States, New YorkUnclaimed profile
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  • China, GuangzhouUnclaimed profile
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  • Netherlands, RotterdamUnclaimed profile
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Suppliers marked Unclaimed profile have not claimed their profile yet. They are not verified by CompoundList, their offers are price on request and details may have changed, so please confirm them with the supplier. Company representatives can claim a profile with a business email on the company's own website domain. Our team verifies each claim and sends the result by email.

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Foscarnet price

Indicative price range per kg from live supplier offers

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Uses and applications

What the substance is used for, by industry and function

Industries and functions

Pharmacological actions

  • Antiviral Agents
  • Reverse Transcriptase Inhibitors

Roles

  • HIV-1 reverse transcriptase inhibitor
  • anti-HIV agent
  • anti-HIV-1 agent
  • antiinfective agent
  • antimicrobial agent
  • antimicrobial drug
  • antiviral agent
  • antiviral drug
  • enzyme inhibitor
  • geroprotector
  • pharmaceutical
  • protective agent
  • sodium-dependent Pi-transporter inhibitor

Pharmacology

Foscarnet is a Pyrophosphate Analog DNA Polymerase Inhibitor. The mechanism of action of foscarnet is as a DNA Polymerase Inhibitor and Chelating Activity.

How it is made

Phosphonoformate is prepared by saponification of the triethyl ester of phosphonoformate with NaOH. Trisodium phosphonoformate hexahydrate is recrystallized from H2O.

Regulatory status

Inventories, regulations and trade controls that list this substance

Health and food

  • Active ingredient in FDA approved drug labels

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Foscarnet is traded under.

HS 2931.49Indicative HS code

Non-halogenated organo-phosphorous derivatives, other

World exports in 2024
$3.44B
−6.5% vs 2023, imports $3.07B
2022 to 2024
Top exporters
  1. China54.9%
  2. United States25.4%
  3. Germany5.1%
Top importers
  1. United States20.9%
  2. Argentina14.9%
  3. Brazil14.3%
Reported customs values in USD, not prices.Full trade data

The HS code shown for Foscarnet is indicative (it was assigned by structure rules). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Foscarnet, based on the data on this page

What is Foscarnet?

Phosphonoformic acid is phosphoric acid in which one of the hydroxy groups is replaced by a carboxylic acid group.

What is the CAS number of Foscarnet?

The CAS registry number of Foscarnet is 4428-95-9. Other or deprecated CAS numbers: 63585-09-1.

What is the molecular formula and weight of Foscarnet?

The molecular formula of Foscarnet is CH3O5P and its molar mass is 126.00 g/mol.

What is Foscarnet used for?

Known uses and roles of Foscarnet include antivirals in pharmaceuticals, hiv-1 reverse transcriptase inhibitor, anti-hiv agent, anti-hiv-1 agent, antiinfective agent and 11 more.

Is Foscarnet hazardous?

Foscarnet carries the GHS signal word "Warning". Main hazards: suspected of causing genetic defects, may cause damage to organs through prolonged or repeated exposure. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Foscarnet?

Foscarnet is usually classified under HS code 293149 (Non-halogenated organo-phosphorous derivatives, other). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Foscarnet?

CompoundList lists 21 suppliers of Foscarnet in China, United States, Germany, Hungary and 2 more. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

What is the price of Foscarnet?

Suppliers quote Foscarnet on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

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Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
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