Corrin

{{Chembox

| verifiedrevid = 443543138

| ImageFile = Corrin.svg

| ImageSize = 220px

| IUPACName = (5Z,9Z,14Z)-2,3,7,8,12,13,17,18,19,22-Decahydro-1H-corrinhttps://pubchem.ncbi.nlm.nih.gov/compound/6438343#section=IUPAC-Name&fullscreen=true

| OtherNames =

| Section1 = {{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 16736705

| InChIKey = WUPRCGRRQUZFAB-DEGKJRJSBL

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C19H22N4/c1-3-14-10-16-5-7-18(22-16)19-8-6-17(23-19)11-15-4-2-13(21-15)9-12(1)20-14/h9-11,18-19,22H,1-8H2/b12-9-,15-11-,16-10-

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = WUPRCGRRQUZFAB-DEGKJRJSSA-N

| CASNo_Ref = {{cascite|correct|??}}

| CASNo=262-76-0

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 288E04GRMT

| PubChem=6438343

| InChI = 1/C19H22N4/c1-3-14-10-16-5-7-18(22-16)19-8-6-17(23-19)11-15-4-2-13(21-15)9-12(1)20-14/h9-11,18-19,22H,1-8H2/b12-9-,15-11-,16-10-

| ChEBI_Ref = {{ebicite|correct|EBI}}

| ChEBI = 33221

| SMILES = N=1C=4CCC=1\C=C2/NC(CC2)C\5CC/C(C=C3\CC/C(=N3)/C=4)=N/5

}}

| Section2 = {{Chembox Properties

| Formula=C₁₉H₂₂N₄

| MolarMass=306.40478

| Appearance=

| Density=

| MeltingPt=

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| Solubility=

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| Section3 = {{Chembox Hazards

| MainHazards=

| FlashPt=

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Corrin is a heterocyclic compound. Although not known to exist on its own, the molecule is of interest as the parent macrocycle related to the cofactor and chromophore in vitamin B₁₂. Its name reflects that it is the "core" of vitamin B₁₂ (cobalamins). Compounds with a corrin core are known as "corrins".Nelson, D. L.; Cox, M. M. "Lehninger, Principles of Biochemistry" 3rd Ed. Worth Publishing: New York, 2000. {{ISBN|1-57259-153-6}}.

There are two chiral centres, which in natural compounds like cobalamin have the same stereochemistry.

Coordination chemistry

Upon deprotonation, the corrinoid ring is capable of binding cobalt. In vitamin B₁₂, the resulting complex also features a benzimidazole-derived ligand, and the sixth site on the octahedron serves as the catalytic center.

The corrin ring resembles the porphyrin ring.{{cite journal |doi=10.1021/cr030720z|title=Chemistry and Enzymology of Vitamin B12 |year=2005 |last1=Brown |first1=Kenneth L. |journal=Chemical Reviews |volume=105 |issue=6 |pages=2075–2150 |pmid=15941210 }} Both feature four pyrrole-like subunits organized into rings. Corrins have a central 15-membered {{chem2|C11N4}} ring whereas porphryins have an interior 16-membered {{chem2|C12N4}} ring. All four nitrogen centers are linked by conjugation structure, with alternating double and single bonds. In contrast to porphyrins, corrins lack one of the carbon groups that link the pyrrole-like units into a fully conjugated structure. With a conjugated system that extends only 3/4 of the way around the ring, and does not include any of the outer edge carbons, corrins have a number of non-conjugated sp³ carbons, making them more flexible than porphyrins and not as flat. A third closely related biological structure, the chlorin ring system found in chlorophyll, is intermediate between porphyrin and corrin, having 20 carbons like the porphyrins and a conjugated structure extending all the way around the central atom, but with only 6 of the 8 edge carbons participating.

Corroles (octadehydrocorrins) are fully aromatic derivatives of corrins.

Corrin

Coordination chemistry

References

Further reading