Serotonin (C10H12N2O): structure, properties and hazards

Names and identifiers

IUPAC name: 3-(2-aminoethyl)-1H-indol-5-ol
Synonyms: 5-HT, 5-hydroxytryptamine, enteramine
+ 37 more
5-HYDROXYTRYPTAMINE, 3-(2-Aminoethyl)-1H-indol-5-ol, Enteramine, Thrombotonin, Thrombocytin, Serotonine, 1H-Indol-5-ol, 3-(2-aminoethyl)-, Hippophaine, 3-(beta-Aminoethyl)-5-hydroxyindole, 333DO1RDJY, DTXSID8075330, CHEBI:28790, 3-(2-Aminoethyl)-1H-indol-5-o, Serotonin (Human), 5 Hydroxytryptamine, Serotonin 1543, RefChem:6493, DTXCID4040765, 200-058-9, NSC58241, Antemovis, Ds substance, Hippophain, 5-Hta, Antemoqua, Substance DS, Substanz DS, Tryptamine, 5-hydroxy-, 3-(2-Aminoethyl)indol-5-ol, Indol-5-ol, 3-(2-aminoethyl)-, Enteramin, 5-Hydroxy-3-(beta-aminoethyl)indole, 3-(2-Amino-ethyl)-1H-indol-5-ol, MFCD00055054, 3-(.beta.-Aminoethyl)-5-hydroxyindole, Lisinopril Impurity 21, 5-Hydroxytryptamine, free base
Molecular formula: C₁₀H₁₂N₂O
Empirical formula: C₁₀H₁₂N₂O
Molecular weight: 176.21 g/mol
Exact mass: 176.09496
CAS number: 50-67-9
PubChem CID: 5202
Canonical SMILES: C1=CC2=C(C=C1O)C(=CN2)CCN
Isomeric SMILES: C1=CC2=C(C=C1O)C(=CN2)CCN
InChI: InChI=1S/C10H12N2O/c11-4-3-7-6-12-10-2-1-8(13)5-9(7)10/h1-2,5-6,12-13H,3-4,11H2
InChIKey: QZAYGJVTTNCVMB-UHFFFAOYSA-N
Molfile

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

Calculated

Heavy atoms: 13
Rings: 2
Aromatic rings: 2
Fraction sp³ carbons (Fsp3): 0.2
H-bond donors: 3
H-bond acceptors: 2
Rotatable bonds: 2
TPSA (Å²): 62
Formal charge: 0
XLogP3: 0.2 PubChem
Complexity: 174 PubChem
Stereocenters: None
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

C68.16%
H6.86%
N15.90%
O9.08%

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: 1.37 Crippen (Wildman and Crippen 1999)
log S (water solubility): -2.18 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 2.13 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 176.22
log P ≤ 5 (Crippen): 1.37
H-bond donors ≤ 5: 3
H-bond acceptors ≤ 10: 2

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

Danger

Most widely reported: 67 company reports to ECHA. Source [1].

Acute toxicity
Health hazard

H301Toxic if swallowed
H361Suspected of damaging fertility or the unborn child (98.5% of reports)

Precautionary statements: P203, P264, P270, P280, P301+P316, P318, P321, P330, P405, P501

Safety data sheets on the supplier’s page: J&H Chemical Co.,ltd, A2B Chem, AA BLOCKS.

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]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[2]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
[3]SpectraBase · 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
[6]NIST Mass Spectrometry Data Center · Linked only · 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

Tryptamine 59%

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