Benzocaine
Athanor · official
C9H11NO2 · 165.19 g/mol
IUPAC name: ethyl 4-aminobenzoate
Also called Orajel, Anbesol, local anaesthetic
DangerMay cause an allergic skin reaction · Causes damage to organs · Toxic to aquatic life with long lasting effectsNames and identifiers
- IUPAC name
- ethyl 4-aminobenzoate
- Synonyms
- Orajel, Anbesol, local anaesthetic
+ 38 more
Ethyl 4-aminobenzoate, Ethyl p-aminobenzoate, Anaesthesin, Parathesin, Norcaine, Americaine, Ethyl aminobenzoate, 4-Aminobenzoic acid ethyl ester, Parathesine, Topcaine, Anesthesin, Anesthone, Hurricaine, Norcain, Orthesin, Anaesthin, Anesthesine, Dermoplast, Identhesin, Amben ethyl ester, p-Carbethoxyaniline, Baby Anbesol, Anaesthan-syngala, Ora-jel, Solu H, 4-Carbethoxyaniline, p-Ethoxycarboxylic aniline, Benzocaina, Benzocainum, Benzoic acid, 4-amino-, ethyl ester, p-(Ethoxycarbonyl)aniline, Ethyl PABA, 4-(Ethoxycarbonyl)aniline, Ethyl p-aminophenylcarboxylate, Anaesthesinum, Aethoform, p-Aminobenzoic acid ethyl ester, Chloraseptic
- Molecular formula
- C9H11NO2
- Empirical formula
- C9H11NO2
- Molecular weight
- 165.19 g/mol
- Exact mass
- 165.07898
- CAS number
- 94-09-7
- PubChem CID
- 2337
- Canonical SMILES
- CCOC(=O)C1=CC=C(C=C1)N
- Isomeric SMILES
- CCOC(=O)C1=CC=C(C=C1)N
- InChI
- InChI=1S/C9H11NO2/c1-2-12-9(11)7-3-5-8(10)6-4-7/h3-6H,2,10H2,1H3
- InChIKey
- BLFLLBZGZJTVJG-UHFFFAOYSA-N
- Molfile
Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.
Physical properties
- Appearance
- Needles from water[2]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source – Dry Powder [1] EPA Chemical Data Reporting (CDR) –shown Needles from water [2] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. V2 1357 - Solubility in water
- Soluble in acid[2]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source –shown Soluble in acid [2] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. V2 1357 – In water, 1,310 mg/L at 25 °C [2] Hazardous Substances Data Bank (HSDB)cites Yalkowsky, S.H., He, Yan., Handbook of Aqueous Solubility Data: An Extensive Compilation of Aqueous Solubility Data for Organic Compounds Extracted from the AQUASOL dATAbASE. CRC Press LLC, Boca Raton, FL. 2003., p. 579 - log P
- log Kow = 1.86[2]
- pKa
- pKa = 2.51 (conjugate acid)[2]
- Vapor pressure
- 2.6 × 10⁻⁴ mmHg at 25 °C (estimated)[2]
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
- 12
- Rings
- 1
- Aromatic rings
- 1
- Fraction sp³ carbons (Fsp3)
- 0.22
- H-bond donors
- 1
- H-bond acceptors
- 3
- Rotatable bonds
- 2 computed here · PubChem 3
- TPSA (Ų)
- 52.3
- Formal charge
- 0
- XLogP3
- 1.9 PubChem
- Complexity
- 151 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
- C65.44%
- H6.71%
- N8.48%
- O19.37%
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
- 1.45 Crippen (Wildman and Crippen 1999)
- log S (water solubility)
- -2.01 ESOL (Delaney 2004), log mol/L
- Synthetic accessibility
- 1.45 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)
Drug-likeness: Lipinski’s rule of five
- Molecular weight ≤ 500: 165.19
- log P ≤ 5 (Crippen): 1.45
- H-bond donors ≤ 5: 1
- H-bond acceptors ≤ 10: 3
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: 351 company reports to ECHA. Source [3].
- Harmful or irritant
- Health hazard
- Environmental hazard
- H317May cause an allergic skin reaction (77.8% of reports)
- H370Causes damage to organs (47.3% of reports)
- H411Toxic to aquatic life with long lasting effects (11.4% of reports)
Precautionary statements: P260, P261, P264, P270, P272, P273, P280, P302+P352, P308+P316, P321, P333+P317, P362+P364, P391, P405, P501
View all classifications (2)
- [3] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 11.1% (39 of 351) of reports.
- [3] European Chemicals Agency (ECHA) · 351 reports · DangerH317, H370, H411
Storage
- Benzocaine topical creams and ointments should be stored in tight containers and protected from light; prolonged exposure to temperatures greater than 30 °C should be avoided.[2]
- Benzocaine topical aersols and solutions should be stored at a temperature less than 40 °C, preferably between 15-30 °C; freezing should be avoided. Because the contents of benzocaine aerosols are under pressure, the aerosol container should not be punctured, used or stored near heat or an open flame, exposed to temperatures greater than 49 °C, or placed into a fire or incinerator for disposal.[2]
Safety data sheets on the supplier’s page: MolCore, LGC Standards, Alfa Chemistry.
Always read the supplier’s safety data sheet before working with it.
Spectra
- NMRHazardous Substances Data Bank (HSDB)
- 1H NMRHuman Metabolome Database (HMDB) (Bruker · 600 MHz · CDCl3) · Human Metabolome Database (HMDB) (JEOL · 90 MHz · CDCl3) · SpectraBase (BRUKER AC-300)
- 13C NMRHuman Metabolome Database (HMDB) (Varian · 25.16 MHz · CDCl3) · SpectraBase
- 15N NMRSpectraBase
- 1H-13C NMRHuman Metabolome Database (HMDB) (Bruker · 600 MHz · CDCl3)
- GC-MSHuman Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (EI-B · positive) · Human Metabolome Database (HMDB) (CI-B · positive) · Human Metabolome Database (HMDB) (EI-B · positive)
- MS-MSHuman Metabolome Database (HMDB) (Negative) · Human Metabolome Database (HMDB) (Positive) · Human Metabolome Database (HMDB) (Positive) · Human Metabolome Database (HMDB) (Negative) · Human Metabolome Database (HMDB) (Positive) · Human Metabolome Database (HMDB) (Positive)
- LC-MSMassBank Europe (Exploris 480 Orbitrap (Thermo Scientific) · LC-ESI-QFT · POSITIVE) · MassBank Europe (Bruker maXis Impact · LC-ESI-QTOF · POSITIVE) · MassBank Europe (Bruker maXis Impact · LC-ESI-QTOF · POSITIVE) · MassBank Europe (Bruker maXis Impact · LC-ESI-QTOF · POSITIVE) · MassBank Europe (Bruker maXis Impact · LC-ESI-QTOF · POSITIVE) · MassBank Europe (Bruker maXis Impact · LC-ESI-QTOF · POSITIVE)
- Other MSMassBank Europe (HITACHI RMU-7M · EI-B · POSITIVE) · MassBank Europe (HITACHI RMU-7 · EI-B · POSITIVE) · MassBank Europe (HITACHI RMU-6D · EI-B · POSITIVE) · MassBank Europe (HITACHI M-60 · EI-B · POSITIVE) · MassBank Europe (HITACHI M-60 · CI-B · POSITIVE) · MassBank Europe (JEOL JMS-DX-300 · EI-B · POSITIVE)
- UVHazardous Substances Data Bank (HSDB)
- IRHazardous Substances Data Bank (HSDB)
- FTIRSpectraBase (Bruker IFS 85 · KBr-Pellet)
- ATR-IRSpectraBase (Bio-Rad FTS · ATR-Neat (DuraSamplIR II))
- Vapor Phase IRSpectraBase (Bruker IFS 85 · Gas-GC)
- RamanSpectraBase (FT-Raman)
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]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
- [2]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
- [3]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
- [4]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
- [5]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
- [6]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
- [7]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
- [8]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.