Emtricitabine is a
(deoxy)cytidine analogue. It has a
fluoride group attached to carbon 5 of the pyrimidine ring of cytosine.
It is called (5-fluoro-)
thiacytidine because it has a sulphur atom in the deoxyribose section, at the
same place that the normal DNA molecule forms phosphodiester bonds with the next nucleotide.
It may be described as
2'-deoxy-5-fluoro-3'-thiacytidine.
It is used as a
nucleoside reverse transcriptase inhibitor (NRTI) because it acts as a selective inhibitor of HIV's reverse transcriptase enzyme, which converts viral RNA into DNA, to be incorporated into human T lymphocyte cells.
Emtricitabine in combination with other drugs can be used as
highly active antiretroviral therapy (HAART) treatments for HIV.