Neostigmine (C12H19N2O2+): structure, properties and hazards

Names and identifiers

IUPAC name: [3-(dimethylcarbamoyloxy)phenyl]-trimethylazanium
Synonyms: Prostigmin, cholinesterase inhibitor, Eustigmin
+ 36 more
Eustigmine, Prostigmine, Vagostigmine, Neostigmin, Juvastigmin, m-Trimethylammoniumphenyldimethylcarbamate, 3-Trimethylammoniumphenyl N,N-dimethylcarbamate, Neostigmine ion, Neostigmine cation, 3-[(dimethylcarbamoyl)oxy]-N,N,N-trimethylanilinium, Neostigmine (cation), (m-Hydroxyphenyl)trimethylammonium dimethylcarbamate, [3-(dimethylcarbamoyloxy)phenyl]-trimethylazanium, 3982TWQ96G, (m-Hydroxyphenyl)trimethylammonium dimethylcarbamate (ester), Ammonium, (m-hydroxyphenyl)trimethyl-, dimethylcarbamate (ester), Benzenaminium, 3-(((dimethylamino)carbonyl)oxy)-N,N,N-trimethyl-, CHEBI:7514, DTXSID1023360, Prozerin, Benzenaminium, 3-[[(dimethylamino)carbonyl]oxy]-N,N,N-trimethyl-, (3-(dimethylcarbamoyloxy)phenyl)-trimethylazanium, 3-((dimethylcarbamoyl)oxy)-N,N,N-trimethylanilinium, RefChem:55701, DTXCID703360, Normastigmin, Synstigmin, Neostigmine [BAN], Neostigmine (BAN), Prostigmin (TN), CHEMBL278020, Neostigminum, [3-(dimethylcarbamoyloxy)phenyl]-trimethyl-azanium bromide, 3-{[(dimethylamino)carbonyl]oxy}-N,N,N-trimethylanilinium, CCRIS 3079, [3-(dimethylcarbamoyloxy)phenyl]-trimethyl-azanium; sulfonatooxymethane
Molecular formula: C₁₂H₁₉N₂O₂+
Empirical formula: C₁₂H₁₉N₂O₂
Molecular weight: 223.29 g/mol
Exact mass: 223.14465
CAS number: 59-99-4
PubChem CID: 4456
Canonical SMILES: CN(C)C(=O)OC1=CC=CC(=C1)[N+](C)(C)C
Isomeric SMILES: CN(C)C(=O)OC1=CC=CC(=C1)[N+](C)(C)C
InChI: InChI=1S/C12H19N2O2/c1-13(2)12(15)16-11-8-6-7-10(9-11)14(3,4)5/h6-9H,1-5H3/q+1
InChIKey: ALWKGYPQUAPLQC-UHFFFAOYSA-N
Molfile

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

Calculated

Heavy atoms: 16
Rings: 1
Aromatic rings: 1
Fraction sp³ carbons (Fsp3): 0.42
H-bond donors: 0
H-bond acceptors: 2
Rotatable bonds: 2 computed here · PubChem 3
TPSA (Å²): 29.5
Formal charge: 1
XLogP3: 1.5 PubChem
Complexity: 246 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

C64.55%
H8.58%
N12.55%
O14.33%

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: 1.94 Crippen (Wildman and Crippen 1999)
log S (water solubility): -2.59 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 2.63 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 223.3
log P ≤ 5 (Crippen): 1.94
H-bond donors ≤ 5: 0
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

No GHS hazard classification was found in the sources.

Safety data sheets on the supplier’s page: MolCore, RR Scientific, BenchChem.

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]NMRShiftDB · Linked only · via PubChem · retrieved 2026-10-14
[2]SpectraBase · Linked only · 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.