Porphine

Porphine or porphin is an organic compound of empirical formula C₂₀H₁₄N₄. It is heterocyclic and aromatic. The molecule is a flat macrocycle, consisting of four pyrrole-like rings joined by four methine bridges, which makes it the simplest of the tetrapyrroles.^[2]

Porphine

Names
IUPAC name Porphyrin[1]
Other names Porphin
Identifiers
CAS Number	101-60-0 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:8337 Y
ChemSpider	10447586 Y
ECHA InfoCard	100.002.690
PubChem CID	66868
UNII	604BGD9J5B Y
CompTox Dashboard (EPA)	DTXSID6059235
InChI InChI=1S/C20H14N4/c1-2-14-10-16-5-6-18(23-16)12-20-8-7-19(24-20)11-17-4-3-15(22-17)9-13(1)21-14/h1-12,21,24H/b13-9-,14-10-,15-9-,16-10-,17-11-,18-12-,19-11-,20-12- Y Key: RKCAIXNGYQCCAL-CEVVSZFKSA-N Y InChI=1/C20H14N4/c1-2-14-10-16-5-6-18(23-16)12-20-8-7-19(24-20)11-17-4-3-15(22-17)9-13(1)21-14/h1-12,21,24H/b13-9-,14-10-,15-9-,16-10-,17-11-,18-12-,19-11-,20-12- Key: RKCAIXNGYQCCAL-CEVVSZFKBA
SMILES C1=CC2=CC5=CC=C(C=C4C=CC(C=C3C=CC(=CC1=N2)N3)=N4)N5
Properties
Chemical formula	C20H14N4
Molar mass	310.35196 g/mol
Appearance	Dark red, shiny leaflets
Melting point	N/A
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

The nonpolar tetrapyrrolic ring structure of porphine means it is poorly soluble in most organic solvents and hardly water soluble.^[3] As a result, porphine is mostly of theoretical interest. It has been detected in GC-MS of certain fractions of Piper betle.^[4]

Porphine derivatives: porphyrins

Further information: Porphyrin

Substituted derivatives of porphine are called porphyrins. Many porphyrins are found in nature with the dominant example being protoporphyrin IX.^[5] Many synthetic porphyrins are also known, including octaethylporphyrin^[6] and tetraphenylporphyrin.^[7]

• Common porphyrins
• 
  Derivatives of protoporphyrin IX are common in nature, the precursor to hemes.
• 
  Octaethylporphyrin (H₂OEP) is a synthetic analogue of protoporphyrin IX. Unlike the natural porphyrin ligands, OEP²⁻ is highly symmetrical.
• 
  Tetraphenylporphyrin (H₂TPP)is another synthetic analogue of protoporphyrin IX. Unlike the natural porphyrin ligands, TPP²⁻ is highly symmetrical. Another difference is that its methine centers are occupied by phenyl groups.

Two resonance structures of porphine.

Further reading

• Budavari, Susan (1989). "7574. Porphine". The Merck Index (11th ed.). Merck & Co., Inc. p. 1210. ISBN 0-911910-28-X. LCCN 89-60001.