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Oseltamivir Phosphate (204255-11-8) C16H31N2O8P

  • Chemical Name:Oseltamivir phosphate
  • CAS No.:204255-11-8
  • MF: C16H31N2O8P
  • MW:410.4
  • Specification: USP|EP|BP
  • Purity: 95%-99% or As customer requested
  • Appearance: white to beige Powder
  • Solubility:Soluble in water and hydrochoric acid.
  • Product Categories:API;Tamiflu;Influenza Viruses;apis;Intermediates & Fine Chemicals;Pharmaceuticals
  • Test method: HPLC

Oseltamivir Phosphate is the phosphate salt of oseltamivir, a synthetic derivative prodrug of ethyl ester with antiviral activity. By blocking neuraminidases on the surfaces of influenza viruses, oseltamivir interferes with host cell release of complete viral particles. (Source: NCI Thesaurus (NCIt))

Oseltamivir phosphate Basic information 

Product Name: Oseltamivir phosphate
Synonyms: Osteltamivir phosphate;(3R,5S)-ethyl 4-acetamido-5-amino-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate phosphate;Oseltamivir phosphat;Oseltamivir Phosphate (200 mg);Oselt;OseltaMivir Acid-D3 Phosphate;OseltaMivir phosphate (TaMiflu);(3R,4R,5S)-ethyl 4-acetaMido-5-aMino-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate phosphate
CAS: 204255-11-8
MF: C16H31N2O8P
MW: 410.4
EINECS: 616-396-9
Product Categories: API;Tamiflu; Influenza Viruses; Amines; Anti-virals; apis; Intermediates & Fine Chemicals; Pharmaceuticals; Oseltamivir
Mol File: 204255-11-8.mol

Osteltamivir phosphate Chemical Structure

Oseltamivir phosphate            

Tamiflu Chemical Properties   
Melting point  196-198°C
storage temp.  -20°C Freezer
solubility  H2O: soluble30mg/mL, clear
form  powder
color  white to beige
optical activity [α]/D -26 to -36°, c = 1 in H2O
CAS DataBase Reference 204255-11-8(CAS DataBase Reference)

Tamiflu Usage And Synthesis

Uses Oseltamivir Phosphate is an orally active inhibitor of influenza virus neuraminidase; converted in vivo to the active acid metabolite. An antiviral drug. It is a COVID19-related research product.
Anti-influenza virus Oseltamivir phosphate is a kind of anti-influenza drugs, under the trade name Tamiflu. Its appearance exhibits as white to yellowish-white powder. It can be divided into type A (alpha) and B (Beta) selective inhibitor of the influenza virus neuraminidase and can prevent the release of virus from infected cells, through inhibiting the activity of the influenza virus neuraminidase, thus achieving the purpose of control of influenza symptoms. Clinically it can be used for treatment of the type A influenza and type B influenza in adults and children of 1 year old or over 1 year old as well as the clinical prevention of influenza A and B in adult and adolescent of 13 year old or over 13 years old.
Oseltamivir phosphate can subject to rapid metabolism into oselatamivr carboxylate after gastrointestinal absorption with 75% of the total oral administrated dose participating in the systemic circulation in the from of oselatamivr carboxylate. The active ingredient of this drug is a potent and unique neuraminidase inhibitors acting on all the processes of influenza virus infection, preventing the replication of all clinically relevant influenza virus strains A or B strain. It has obvious inhibitory effect even in nanomolar concentration in vitro. It has ben observed in vitro that the active metabolite can inhibit the growth of influenza virus as well as in vivo that it can inhibit the replication and pathogenicity of influenza virus. This product, through inhibiting the release of virus from infected cells, can reduce the spread of influenza A or B virus.
The above information is edited by the chemicalbook of Dai Xiongfeng.
Uses Antibiotics and anti-virus
Description Oseltamivir was launched in the US and Switzerland for the treatment of influenza infections by all common strain viruses. It can be obtained by at least 2 different ways including a novel 12-step synthesis from (-)-quinic acid. Oseltamivir is the ethyl ester prodrug of GS-4071, the corresponding acid, which is one of the most potent inhibitors of both influenza A and B virus neuraminidase (sialidase) isoenzymes; these glycoproteins are expressed on the virion surface and are essential for virus replication for both A and B strains. Oseltamivir emerged as one of the first two neuraminidase inhibitors to reach the market. GS-4071 demonstrated a low (< 5%) oral bioavailability in animals due to a poor absorption from the gastrointestinal barrier; by incorporating a more lipophilic ester group, the oral bioavailabilty can reach 30 to 100% in mice, rats and dogs. Following oral administration of Oseltamivir in rats, a similar concentration of GS-4071 was found in the bronchoalveolar lining fluid and the plasma which indicated a good penetration of the active compound into the lower respiratory tract. In mice, chickens and ferrets, orally administered Oseltamivir was found to have significant inhibitory effects on A and B influenza infections in protecting against a lethal challenge of virus and lessening virus titer in the lungs or nasal washings. In several clinical trials with patients receiving oral capsules daily, Oseltamivir was shown to be effective in reducing significantly the duration and severity of the clinical symptoms, including fever, cough and general malaise, in both early treatment and prevention.
Chemical Properties White Cyrstalline Solid


Orally active inhibitor of influenza virus neuraminidase; converted in vivo to the active acid metabolite. An antiviral drug.
Oseltamivir phosphate (Tamiflu) is a competitive neuraminidase inhibitor. The prodrug oseltamivir phosphate (Tamiflu) is itself not virally effective; however, once in the liver, it is converted by natural chemical processes, hydrolysed hepatically to its
An antiviral agent

MSDS: MSDS available

COA: COA can be available if you send us inquiry.

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