A summary of the most common chemical descriptors (InChI Key and SMILES codes) for Antipyrine are summarized together with 3D and 2D structures and relevant physico-chemical properties.

What is the Antipyrine?

The molecule Antipyrine presents a molecular formula of C11H12N2O and its IUPAC name is 1,5-dimethyl-2-phenylpyrazol-3-one.

Antipyrine is an organic compound with the chemical formula C11H12N2O. It is a white solid that is soluble in water and ethanol. Antipyrine is a member of the phenazine class of compounds..

Phenazines are a class of heterocyclic compounds that contain a phenyl ring fused to a nitrogen-containing heterocycle. Antipyrine contains a phenyl ring fused to a pyridine ring. Antipyrine is structurally similar to other phenazines such as phenacetin and acetophenetidin..

Phenazines are known to have a wide range of pharmacological activities. Antipyrine has analgesic, antipyretic, and anti-inflammatory activity. It is also used as an antiparkinsonian agent..

The exact mechanism of action of antipyrine is not known. However, it is thought to work by inhibiting the activity of cyclooxygenase (COX) enzymes. COX enzymes are involved in the synthesis of prostaglandins. Prostaglandins are mediators of inflammation..

The use of antipyrine has been declining due to the availability of more effective and safer drugs. Antipyrine is no longer recommended for the treatment of pain, fever, or inflammation. It is still used as an antiparkinsonian agent in some countries..

Possible side effects of antipyrine include dizziness, drowsiness, headache, nausea, and vomiting. Antipyrine can also cause allergic reactions..

3D structure

Cartesian coordinates

Geometry of Antipyrine in x, y and z coordinates (Å units) to copy/paste elsewhere. Generated with Open Babel software.

2D drawing


Antipyrine VEQOALNAAJBPNY-UHFFFAOYSA-N chemical compound 2D structure molecule svg


Molecule descriptors

IUPAC name1,5-dimethyl-2-phenylpyrazol-3-one
InChI codeInChI=1S/C11H12N2O/c1-9-8-11(14)13(12(9)2)10-6-4-3-5-7-10/h3-8H,1-2H3

Other names (synonyms)

IUPAC nomenclature provides a standardized method for naming chemical compounds. Although this system is widely used in chemistry, many chemical compounds have also other names commonly used in different contexts. These synonyms can come from a variety of sources and are used for a variety of purposes.

One common source of synonyms for chemical compounds is the common or trivial names, assigned on the basis of appearance, properties, or origin of the molecule.

Another source of synonyms are historical or obsolete names employed in the past, however replaced nowadays by more modern or standardized names.

In addition to common and historical names, chemical compounds may also have synonyms that are specific to a particular field or industry.

  • .beta.-Antipyrine
  • 1,2-Dihydro-1,5-dimethyl-2-phenyl-3H-pyrazol-3-one
  • 1,2-Dihydro-1,5-dimethyl-2-phenyl-3H-pyrazol-3-one; Phenazone
  • 1,5-Dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one
  • 1,5-Dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one #
  • 1,5-Dimethyl-2-phenyl-3-pyrazolone
  • 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one
  • 1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one
  • 1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one
  • 1,5-dimethyl-2-phenyl-pyrazol-3-one
  • 1,5-dimethyl-2-phenylpyrazol-3-one
  • 1-Phenyl-2,3-dimethyl-5-pyrazolone
  • 1-Phenyl-2,3-dimethylpyrazole-5-one
  • 2,3-Dimethyl-1-phenyl-3-pyrazolin-5-one
  • 2,3-Dimethyl-1-phenyl-5-pyrazolone
  • 3-Antipyrine
  • 3H-Pyrazol-3-one, 1,2-dihydro-1,5-dimethyl-2-phenyl-
  • 60-80-0
  • A19580
  • A936893
  • AF-960/00437050
  • AI3-15293
  • AS-13248
  • Analgesine
  • Anodynin
  • Anodynine
  • Antipirin
  • Antipyrien
  • Antipyrin
  • Antipyrine
  • Antipyrine (JP17/USP)
  • Antipyrine Crystals
  • Antipyrine, tested according to Ph.Eur.
  • Antipyrinum
  • Apirelina
  • Azophen
  • Azophene
  • Azophenum
  • BDBM50103600
  • BIM-0051287.0001
  • BPBio1_000107
  • BSPBio_000097
  • BSPBio_001870
  • CCG-38904
  • CCRIS 1369
  • CS-2044
  • D01776
  • D1876
  • DB01435
  • DSSTox_CID_1117
  • DSSTox_GSID_21117
  • DSSTox_RID_75949
  • Dimethyloxychinizin
  • Dimethyloxyquinazine
  • DivK1c_000484
  • EC 200-486-6
  • Epitope ID:124927
  • F2173-0728
  • FT-0609690
  • FT-0662246
  • Fenazon
  • Fenazona
  • Fenazone
  • H11233
  • HMS1568E19
  • HMS1920E09
  • HMS2091K09
  • HMS2095E19
  • HMS2272G04
  • HMS3652C09
  • HMS3712E19
  • HMS3885C11
  • HMS501I06
  • HY-B0171
  • IDI1_000484
  • KBio1_000484
  • KBio2_000438
  • KBio2_003006
  • KBio2_005574
  • KBio3_001370
  • KBioGR_000624
  • KBioSS_000438
  • MFCD00003146
  • MLS001331753
  • MLS001332401
  • MLS001332402
  • MLS002154179
  • Methozin
  • NCGC00016274-01
  • NCGC00016274-02
  • NCGC00016274-03
  • NCGC00016274-04
  • NCGC00016274-05
  • NCGC00016274-06
  • NCGC00016274-07
  • NCGC00016274-09
  • NCGC00016274-10
  • NCGC00094591-01
  • NCGC00094591-02
  • NCGC00094591-03
  • NCGC00178937-01
  • NCGC00178937-02
  • NCGC00256527-01
  • NCGC00259149-01
  • NINDS_000484
  • NSC 7945
  • NSC-755874
  • NSC-7945
  • NSC755874
  • NSC7945
  • Oxydimethylquinazine
  • Oxydimethylquinizine
  • Parodyne
  • Pharmakon1600-01500128
  • Phenazon
  • Phenazone
  • Phenazone (INN)
  • Phenazone (pharmaceutical)
  • Phenazone;Phenazon
  • Phenazonum
  • Phenozone
  • Phenylon
  • Phenylone
  • Prestwick0_000029
  • Prestwick1_000029
  • Prestwick2_000029
  • Prestwick3_000029
  • Prestwick_26
  • Pyrazophyl
  • Q-201552
  • Q415578
  • SBI-0051287.P003
  • SMR000238140
  • SPECTRUM1500128
  • SR-05000001566
  • SR-05000001566-1
  • SR-05000001566-3
  • STK328171
  • SW196343-3
  • Sedatin
  • Sedatine
  • T3CHA1B51H
  • WLN: T5NNVJ A1 BR& E1
  • Z56869297
  • antipyrine
  • component of Auralgan
  • s3173

Reference codes for other databases

There exist several different chemical codes commonly used in orded to identify molecules:
  • ZINC61044
  • CAS-60-80-0
  • AKOS000588788
  • BRD-K46937689-001-05-1
  • BRD-K46937689-001-08-5
  • DTXSID6021117
  • CHEMBL277474
  • CHEBI:31225
  • Tox21_110342
  • Tox21_201600
  • Tox21_303026
  • Tox21_110342_1
  • EINECS 200-486-6
  • SPBio_000016
  • SPBio_002018
  • SCHEMBL20452
  • Spectrum_000058
  • Spectrum2_000088
  • Spectrum3_000305
  • Spectrum4_000152
  • Spectrum5_000842

Physico-Chemical properties

IUPAC name1,5-dimethyl-2-phenylpyrazol-3-one
Molecular formulaC11H12N2O
Molecular weight188.226
Melting point (ºC)
Boiling point (ºC)
Density (g/cm3)
Molar refractivity56.26
Topological polar surface area26.9

LogP and topological polar surface area (TPSA) values were estimated using Open Babel software.

The n-octanol/water partition coeficient (Kow) data is applied in toxicology and drug research. Kow values are used, to guess the environmental fate of persistent organic pollutants. High partition coefficients values, tend to accumulate in the fatty tissue of organisms. Molecules with a log(Kow) (or LogP) greater than 5 are considered to bioaccumulate.

TPSA values are the sum of the surface area over all polar atoms or molecules, mainly oxygen and nitrogen, also including hydrogen atoms.

In medicinal chemistry, TPSA is used to assess the ability of a drug to permeabilise cells.

For molecules to penetrate the blood-brain barrier (and act on receptors in the central nervous system), TPSA values below 90 Å2 are required. Thus, molecules with a polar surface area greater than 140 Å2 tend to be poorly permeable to cell membranes.