CAS No.: 196618-13-0

Molecular formula: C16H28N2O4

Molecular weight: 312.4

Anti-influenza drug: oseltamivir phosphate is an anti-influenza drug of neuraminidase inhibitor, marketed in 1999, with the trade name Tamiflu (Tamiflu, also known as "Tamiflu"). It was first discovered by Gilead Sciences, then jointly developed with Roche and approved for listing in the United States. Oseltamivir phosphate is the first oral effective neuraminidase inhibitor, which is effective against influenza A and B viruses. After oral oseltamivir is rapidly converted into its active metabolite, oseltamivir carboxylic acid, by liver and intestinal esterase catalysis. The configuration of oseltamivir carboxylic acid is similar to the transition state of neuraminic acid, which can competitively combine with the active site of influenza virus neuraminidase (NA). Therefore, oseltamivir is a powerful and highly selective influenza virus NA inhibitor (NAIs), which is mainly released from infected host cells by interfering with the virus, So as to reduce the transmission of influenza A or B virus. Therefore, oseltamivir phosphate is a precursor drug. At present, oseltamivir phosphate (Tamiflu) is still recognized as one of the most effective drugs for the treatment of influenza A (H1N1) among the drugs already on the market. It was approved for marketing in China in July 2004.

Pharmacological effect: oseltamivir phosphate is the drug precursor of its active metabolite, and its active metabolite (oseltamivir carboxylate) is a selective influenza virus neuraminidase inhibitor. Neuraminidase is a kind of glycoprotein on the surface of virus. Its activity is crucial for the release of newly formed virus particles from infected cells and the further spread of infectious virus in human body. The active metabolite of oseltamivir phosphate can inhibit the neuraminidase activity of influenza A and B viruses. In vitro, the half inhibitory concentration of viral neuraminidase activity was as low as the level of nanogram. Active metabolites were observed to inhibit the growth of influenza virus in vitro, and also to inhibit the replication and pathogenicity of influenza virus in vivo. This product reduces the spread of influenza A or B virus by inhibiting the release of virus from infected cells. Studies on naturally acquired and laboratory influenza have shown that the use of oseltamivir phosphate does not affect the normal humoral immune response of the human body to infection. Antibody responses to inactivated vaccines were not affected by oseltamivir phosphate treatment.