Pyridine
An azaarene comprising a benzene core in which one -CH group is replaced by a nitrogen atom. It is the parent compound of the class pyridines. — ChEBI
Safety documents & references
2 indexed referencesFind a product-specific SDS
Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.
Identity & molecular properties
Source-linked values| CAS number | 110-86-1 | ChEBI ↗ |
| Molecular formula | C5H5N | ChEBI ↗ |
| Molar mass | 79.102 g/mol | ChEBI ↗ |
| Monoisotopic mass | 79.0422 Da | ChEBI ↗ |
| Formal charge | 0 | ChEBI ↗ |
| ChEBI identifier | CHEBI:16227 | ChEBI ↗ |
Cross-source molecular data
PubChem| Molar mass | 79.10 g/mol | PubChem ↗ |
| Exact mass | 79.042199164 Da | PubChem ↗ |
| Computed XLogP | 0.7 | PubChem ↗ |
| Topological polar surface area (Ų) | 12.9 | PubChem ↗ |
| H-bond donors | 0 | PubChem ↗ |
| H-bond acceptors | 1 | PubChem ↗ |
| Rotatable bonds | 0 | PubChem ↗ |
PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.
Names & structural identifiers
Copy any identifierpyridinepyridineJUJWROOIHBZHMG-UHFFFAOYSA-Nc1ccncc1InChI=1S/C5H5N/c1-2-4-6-5-3-1/h1-5HClassification & relationships
ChEBI ontologyRoles recorded in ChEBI
Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.
Safety classification · Japan
NITE / Japanese governmentPyridine · R02-B-035-MHLW, MOE
| Endpoint | Reported classification |
|---|---|
| Flammable liquids | Category 2 |
| Acute toxicity （Oral） | Category 4 |
| Acute toxicity （Dermal） | Category 4 |
| Acute toxicity （Inhalation: Vapours） | Category 4 |
| Skin corrosion/irritation | Category 1 |
| Serious eye damage/eye irritation | Category 1 |
Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.
Read the original NITE classificationMass ↔ amount of substance
Calculated from sourced massUses 79.102 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.
Elemental composition
Theoretical mass fractionsCNHCalculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.
Research & patent references
Selected source associationsSources & record history
Checked 27 Sep 2026Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0
PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.