Pyrimidine
Athanor · official
C4H4N2 · 80.09 g/mol
Also called 1,3-diazine, metadiazine
DangerFlammable liquid and vapor · Causes serious eye damageNames and identifiers
- IUPAC name
- pyrimidine
- Synonyms
- 1,3-diazine, metadiazine, 1,3-Diazine
+ 37 more
Metadiazine, m-Diazine, Miazine, Pyrimidine base, 1,3-Diazin, K8CXK5Q32L, NSC-89305, DTXSID1051228, CHEBI:16898, RefChem:6186, DTXCID4029850, 206-026-0, 1,3-Diazabenzene, MFCD00006059, pyrimidine phase I, NSC89305, pyrimidine phase II, pyrimidine phase IV, Pyrimidine, dimer, 2,4-Dideoxyuracil, EINECS 206-026-0, NSC 89305, UNII-K8CXK5Q32L, pyrimidin, 13-Diazabenzene, 1,3-Diazabenzene; 1,3-Diazine; Metadiazine; Miazine; NSC 89305; m-Diazine, Pyrimidine free base, Buspirone Impurity 39, PYRIMIDINE [MI], Epitope ID:140100, EC 206-026-0, Pyrimidine, >=98.0%, SCHEMBL1846, SCHEMBL3246, SCHEMBL8375, SCHEMBL9030, SCHEMBL50561
- Molecular formula
- C4H4N2
- Empirical formula
- C2H2N
- Molecular weight
- 80.09 g/mol
- Exact mass
- 80.03745
- CAS number
- 289-95-2
- PubChem CID
- 9260
- Canonical SMILES
- C1=CN=CN=C1
- Isomeric SMILES
- C1=CN=CN=C1
- InChI
- InChI=1S/C4H4N2/c1-2-5-4-6-3-1/h1-4H
- InChIKey
- CZPWVGJYEJSRLH-UHFFFAOYSA-N
- Molfile
Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.
Physical properties
- Appearance
- Liquid[1]
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
- 6
- Rings
- 1
- Aromatic rings
- 1
- Fraction sp³ carbons (Fsp3)
- 0
- H-bond donors
- 0
- H-bond acceptors
- 2
- Rotatable bonds
- 0
- TPSA (Ų)
- 25.8
- Formal charge
- 0
- XLogP3
- -0.4 PubChem
- Complexity
- 32 PubChem
- Stereocenters
- None
- Double-bond geometry
- None specified
- Point group
- C2v of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)
Elemental analysis
- C59.99%
- H5.03%
- N34.98%
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
- 0.48 Crippen (Wildman and Crippen 1999)
- log S (water solubility)
- -1.38 ESOL (Delaney 2004), log mol/L
- Synthetic accessibility
- 2.05 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)
Drug-likeness: Lipinski’s rule of five
- Molecular weight ≤ 500: 80.09
- log P ≤ 5 (Crippen): 0.48
- 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 [2].
- Flammable
- Corrosive
- H226Flammable liquid and vapor (98.3% of reports)
- H318Causes serious eye damage (25% of reports)
Precautionary statements: P210, P233, P240, P241, P242, P243, P264+P265, P280, P303+P361+P353, P305+P354+P338, P317, P370+P378, P403+P235, P501
Safety data sheets on the supplier’s page: SynHet - Synthetic Heterocycles, BenchChem, LGC Standards.
Always read the supplier’s safety data sheet before working with it.
Spectra
- NMRNMRShiftDB
- 1H NMRHuman Metabolome Database (HMDB) (Bruker · 600 MHz · Water) · SpectraBase (Varian CFT-20)
- 13C NMRSpectraBase
- 15N NMRSpectraBase
- 1H-13C NMRHuman Metabolome Database (HMDB) (Bruker · 600 MHz · Water)
- GC-MSNIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · SpectraBase
- MS-MSHuman Metabolome Database (HMDB) (positive)
- LC-MSMassBank Europe (TQD, Waters · LC-ESI-QQ · POSITIVE) · MassBank Europe (TQD, Waters · LC-ESI-QQ · POSITIVE) · MassBank of North America (MoNA) (Quattro_QQQ · positive) · MassBank of North America (MoNA) (Quattro_QQQ · positive) · MassBank of North America (MoNA) (Quattro_QQQ · positive)
- Other MSMassBank of North America (MoNA) (TQD, Waters · Flow-injection QqQ/MS · ESI) · MassBank of North America (MoNA) (TQD, Waters · Flow-injection QqQ/MS · ESI)
- FTIRSpectraBase (CAPILLARY CELL: 0.015 MM)
- ATR-IRSpectraBase (Bruker Tensor 27 FT-IR · ATR-Neat (DuraSamplIR II))
- Vapor Phase IRSpectraBase (DIGILAB FTS-14 · Vapor Phase)
- RamanSpectraBase (Bruker MultiRAM Stand Alone FT-Raman Spectrometer · 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]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
- [3]NMRShiftDB · Linked only · 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]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
- [7]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
- [8]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.