Oseltamivir phosphate

February 13, 2018
I might not treat the flu as well as you think.
What molecule am I?
Image of Oseltamivir phosphate 3D Image of Oseltamivir phosphate

The 2017–2018 flu season is seeing record numbers of cases, hospitalizations, and pediatric deaths.  Oseltamivir phosphate (usually shortened to oseltamivir), a prescription drug used to prevent and treat influenza, is in high demand. Best known by its trade name Tamiflu, it can be effective against influenza A and influenza B, which are genera of the Orthomyxoviridae virus family.

Oseltamivir, even when it does work, reduces the duration of flu symptoms by only 12–24 h. Some people take it prophylactically, but the US Centers for Disease Control and Prevention does not recommend this practice because it may cause the viruses to develop resistance to the drug. The exception is that high-risk individuals should take it if they have not been (or have only recently been) vaccinated and have been exposed to flu in the previous 48 h.

The irony is that many, if not most, high-risk people are more than 65 years old. But oseltamivir does not work as well in seniors as it does with younger people.

Oseltamivir phosphate hazard information

Serious eye damage/eye irritation, category 2A
H319—Causes serious eye irritation Chemical Safety Warning
GHS classification: skin sensitization, category 1
H317— May cause an allergic skin reactionChemical Safety Toxicity Warning
GHS classification: hazardous to the aquatic environment, category 3
H412— Harmful to aquatic life with long-lasting effectsChemical Safety Warning

*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.

Oseltamivir phosphate
fast facts

CAS Reg. No.204255-11-8
Molar mass410.40 g/mol
Empirical formulaC16H28N2O4•H3O4P
AppearanceWhite crystals 
Melting point190–206 ºC*
Water solubility1.6 g/L (est)

*Wide range of reported melting points

MOTW update

Perfluorooctanoic acid (PFOA) was the Molecule of the Week for August 10, 2015. It is widely used in the production of polytetrafluoroethylene (Teflon) and microchips, but it is being phased out because it is a significant contaminant in drinking water.

In 2010, DuPont introduced GenX, another perfluorinated surfactant, as a “sustainable” replacement for PFOA. But water in the river downstream from the Fayetteville, NC, plant where Nemours (DuPont’s successor) manufactures GenX is contaminated with fluorochemicals. Even after Nemours began to collect its wastewater for disposal in a deep injection well in Texas, perfluorinated ethers such as GenX are mysteriously being detected in the river

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