DangerFlammable solid · Harmful if swallowed · Causes skin irritation · Causes serious eye irritation · Harmful if inhaled · May cause respiratory irritationNames and identifiers
- IUPAC name
- 1,3-benzoxazole
- Synonyms
- 1,3-Benzoxazole, 1-Oxa-3-aza-1H-indene, 1-Oxa-3-azaindene
+ 35 more
Benzoxazoles, NSC-3982, CHEBI:38814, J233Y1I55I, DTXSID8059768, RefChem:388827, DTXCID5037654, CHEBI:46700, 205-988-9, BENZO[D]OXAZOLE, USAF EK-5017, NSC 3982, MFCD00005765, 1,3-Benzoxazole #, AI3-05743, NSC3982, SCHEMBL7903, B0095, EN300-20396, H10149, Q761111, EINECS 205-988-9, UNII-J233Y1I55I, Benzoxazole, 98%, A3423, SCHEMBL2223, SCHEMBL5739, WLN: T56 BN DOJ, A819031, SCHEMBL23760, SCHEMBL29650, SCHEMBL30243, SCHEMBL449019, SCHEMBL449146, SCHEMBL449332
- Molecular formula
- C7H5NO
- Empirical formula
- C7H5NO
- Molecular weight
- 119.12 g/mol
- Exact mass
- 119.03711
- CAS number
- 273-53-0
- PubChem CID
- 9228
- Canonical SMILES
- C1=CC=C2C(=C1)N=CO2
- Isomeric SMILES
- C1=CC=C2C(=C1)N=CO2
- InChI
- InChI=1S/C7H5NO/c1-2-4-7-6(3-1)8-5-9-7/h1-5H
- InChIKey
- BCMCBBGGLRIHSE-UHFFFAOYSA-N
- Molfile
Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.
Calculated
- Heavy atoms
- 9
- Rings
- 2
- Aromatic rings
- 2
- Fraction sp³ carbons (Fsp3)
- 0
- H-bond donors
- 0
- H-bond acceptors
- 2
- Rotatable bonds
- 0
- TPSA (Ų)
- 26
- Formal charge
- 0
- XLogP3
- 1.6 PubChem
- Complexity
- 105 PubChem
- Stereocenters
- None
- Double-bond geometry
- None specified
- Point group
- Cs of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)
Elemental analysis
- C70.58%
- H4.23%
- N11.76%
- O13.43%
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
- 1.83 Crippen (Wildman and Crippen 1999)
- log S (water solubility)
- -2.47 ESOL (Delaney 2004), log mol/L
- Synthetic accessibility
- 2.1 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)
Drug-likeness: Lipinski’s rule of five
- Molecular weight ≤ 500: 119.12
- log P ≤ 5 (Crippen): 1.83
- 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
Danger
Most widely reported: 60 company reports to ECHA. Source [1].
- Flammable
- Harmful or irritant
- H228Flammable solid (10% of reports)
- H302Harmful if swallowed (78.3% of reports)
- H315Causes skin irritation (93.3% of reports)
- H319Causes serious eye irritation (93.3% of reports)
- H332Harmful if inhaled (21.7% of reports)
- H335May cause respiratory irritation (91.7% of reports)
Precautionary statements: P210, P240, P241, P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P317, P319, P321, P330, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P405, P501
Safety data sheets on the supplier’s page: Activate Scientific, Smolecule, Matrix Scientific.
Always read the supplier’s safety data sheet before working with it.
Spectra
- NMRNMRShiftDB
- 1H NMRSpectraBase (BRUKER AC-300)
- 13C NMRSpectraBase
- 15N NMRSpectraBase
- GC-MSNIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · SpectraBase
- MS-MSHuman Metabolome Database (HMDB) (n/a · positive) · NIST Mass Spectrometry Data Center (IT/ion trap)
- UV-VISSpectraBase
- FTIRSpectraBase (NEAT)
- ATR-IRSpectraBase (ATR-Cylindrical Internal Reflectance (CIR))
- Vapor Phase IRSpectraBase (Vapor Phase)
- RamanSpectraBase
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]NMRShiftDB · Linked only · via PubChem · retrieved 2026-10-14
- [3]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
- [4]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
- [5]Human Metabolome Database (HMDB) · 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.