Emtricitabine (C8H10FN3O3S): structure, properties and hazards

Names and identifiers

IUPAC name: 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]pyrimidin-2-one
Synonyms: FTC, Emtriva, Truvada
+ 38 more
HIV, Coviracil, 4-amino-5-fluoro-1-((2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl)pyrimidin-2(1H)-one, 524W91, dOTFC, BW-524W91, 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]pyrimidin-2-one, 2-FTC, (-)-2'-Deoxy-5-fluoro-3'-thiacytidine, (-)-emtricitabine, 2'-Deoxy-5-fluoro-3'-thiacytidine, Emtricitabina, Emtricitabinum, Emtricitabine, (-)-, DTXSID0040129, CHEBI:31536, (-)-beta-2',3'-dideoxy-5-fluoro-3'-thiacytidine, (2R-cis)-4-Amino-5-fluoro-1-(2-(hydroxymethyl)-1,3-oxathiolan-5-yl)-2(1H)-pyrimidinone, 2'-Deoxy-5-fluoro-3'-oxa-4'-thiocytidine, G70B4ETF4S, 5-Fluoro-1-((2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl)cytosine, 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]pyrimidin-2(1H)-one, 524-W-91, (-)-cis-4-amino-5-fluoro-1-(2-hydroxymethyl-1,3-oxathiolan-5-yl)-(1H)-pyrimidin-2-one, 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-1,2-dihydropyrimidin-2-one, DTXCID8020129, (-)-(2R,5S)-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine, ODEFSEY COMPONENT EMTRICITABINE, TRUVADA COMPONENT EMTRICITABINE, EVIPLERA COMPONENT EMTRICITABINE, STRIBILD COMPONENT EMTRICITABINE, 2(1H)-Pyrimidinone, 4-amino-5-fluoro-1-(2-(hydroxymethyl)-1,3-oxathiolan-5-yl)-, (2R-cis)-, 5-Fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine, 2(1H)-Pyrimidinone, 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-, 4-Amino-5-fluoro-1-((2R,5S)-2-hydroxymethyl-[1,3]oxathiolan-5-yl)-1H-pyrimidin-2-one, 2(1H)-PYRIMIDINONE, 4-AMINO-5-FLUORO-1-((2R,5S)-2-(HYDROXYMETHYL)-1,3-OXATHIOLAN-5-YL)-, (-)-(2R,5S)-5-fluoro-1-(2-(hydroxymethyl)-1,3-oxathiolan-5-yl)cytosine, 4-amino-5-fluoro-1-((2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl)pyrimidin-2-one
Molecular formula: C₈H₁₀FN₃O₃S
Empirical formula: C₈H₁₀FN₃O₃S
Molecular weight: 247.25 g/mol
Exact mass: 247.04269
CAS number: 143491-57-0
PubChem CID: 60877
Canonical SMILES: C1C(OC(S1)CO)N2C=C(C(=NC2=O)N)F
Isomeric SMILES: C1[C@H](O[C@H](S1)CO)N2C=C(C(=NC2=O)N)F
InChI: InChI=1S/C8H10FN3O3S/c9-4-1-12(8(14)11-7(4)10)5-3-16-6(2-13)15-5/h1,5-6,13H,2-3H2,(H2,10,11,14)/t5-,6+/m0/s1
InChIKey: XQSPYNMVSIKCOC-NTSWFWBYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

Appearance: White to off white powder[1]
Solubility in water: About 1.12 × 10⁶ mg/L in water at 25 °C[1]
log P: log Kow = -0.43[1]
pKa: pKa = 2.65 (amine)[1]

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 16
Rings: 2
Aromatic rings: 1
Fraction sp³ carbons (Fsp3): 0.5
H-bond donors: 2
H-bond acceptors: 6 computed here · PubChem 5
Rotatable bonds: 2
TPSA (Å²): 90.4 computed here · PubChem 113
Formal charge: 0
XLogP3: -0.6 PubChem
Complexity: 374 PubChem
Stereocenters: 2 definedCIP: C7: S · C10: R
Double-bond geometry: None specified
Point group: C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C38.86%
H4.08%
F7.68%
N17.00%
O19.41%
S12.97%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: -0.46 Crippen (Wildman and Crippen 1999)
log S (water solubility): -1.23 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 3.89 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 247.25
log P ≤ 5 (Crippen): -0.46
H-bond donors ≤ 5: 2
H-bond acceptors ≤ 10: 6

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

This chemical does not meet GHS hazard criteria for 100% (6 of 6) of all reports.[2]

Storage

Store at 25 °C (77 °F); excursions permitted to 15 °C-30 °C (59 °F-86 °F)[1]

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[2]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[3]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
[4]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
[5]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.

Similar structures

Lamivudine 63%

Tanimoto similarity on Morgan fingerprints (radius 2) with RDKit 2026.09, at least 45%.