Pipecolic acid

Pipecolic acid (piperidine-2-carboxylic acid) is an organic compound with the formula HNC₅H₉CO₂H. It is a carboxylic acid derivative of piperidine and, as such, an amino acid, although not one encoded genetically. Like many other α-amino acids, pipecolic acid is chiral, although the S-stereoisomer is more common. It is a colorless solid.

Pipecolic acid

Names
Preferred IUPAC name Piperidine-2-carboxylic acid
Identifiers
CAS Number	3105-95-1 (2S) Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:17964 N
ChemSpider	826 N
ECHA InfoCard	100.007.835
EC Number	217-024-4
KEGG	C00408 N
MeSH	C031345
PubChem CID	849
UNII	69374CKB33 Y
CompTox Dashboard (EPA)	DTXSID40862144
InChI InChI=1S/C6H11NO2/c8-6(9)5-3-1-2-4-7-5/h5,7H,1-4H2,(H,8,9) N Key: HXEACLLIILLPRG-UHFFFAOYSA-N N InChI=1/C6H11NO2/c8-6(9)5-3-1-2-4-7-5/h5,7H,1-4H2,(H,8,9) Key: HXEACLLIILLPRG-UHFFFAOYAL
SMILES C1CCNC(C1)C(=O)O
Properties
Chemical formula	C6H11NO2
Molar mass	129.15704
Appearance	white or colorless solid
Melting point	268 °C (514 °F; 541 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Its biosynthesis starts from lysine.^[1] CRYM, a taxon-specific protein that also binds thyroid hormones, is involved in the pipecolic acid pathway.

Medicine

It accumulates in pipecolic acidemia. Elevation of pipecolic acid can be associated with some forms of epilepsy, such as pyridoxine-dependent epilepsy.^[2][3]

Occurrence and reactions

Like most amino acids, pipecolic acid is a chelating agent. One complex is Cu(HNC₅H₉CO₂)₂(H₂O)₂.^[4]

Pipecolic acid was identified in the Murchison meteorite.^[5] It also occurs in the leaves of the genus Myroxylon, a tree from South America.^[6]

See also

• Bupivacaine
• Efrapeptin

References

1. Gatto, Gregory J.; Boyne, Michael T.; Kelleher, Neil L.; Walsh, Christopher T. (2006). "Biosynthesis of Pipecolic Acid by RapL, a Lysine Cyclodeaminase Encoded in the Rapamycin Gene Cluster". Journal of the American Chemical Society. 128 (11): 3838–3847. doi:10.1021/ja0587603. PMID 16536560.
2. Plecko B, Hikel C, Korenke GC, et al. (2005). "Pipecolic acid as a diagnostic marker of pyridoxine-dependent epilepsy". Neuropediatrics. 36 (3): 200–5. doi:10.1055/s-2005-865727. PMID 15944906.
3. Kaminiów K, Pająk M, Pająk R, Paprocka J (December 2021). "Pyridoxine-Dependent Epilepsy and Antiquitin Deficiency Resulting in Neonatal-Onset Refractory Seizures". Brain Sciences. 12 (1): 65. doi:10.3390/brainsci12010065. PMC 8773593. PMID 35053812.
4. Hockless, David C.R.; Mayadunne, Renuka C.; Wild, S.Bruce (1995). "Convenient resolution of (±)-piperidine-2-carboxylic acid ((±)-pipecolic acid) by separation of palladium(II) diastereomers containing orthometallated (S)-(−)-1-[1-(dimethylamino)ethyl]naphthalene". Tetrahedron: Asymmetry. 6 (12): 3031–3037. doi:10.1016/0957-4166(95)00400-9.
5. Kvenholden, Keith A.; Lawless, James G.; Ponnamperuma, Cyril (February 1971). "Nonprotein Amino Acids in the Murchison Meteorite". Proceedings of the National Academy of Sciences. 68 (2): 486–490. Bibcode:1971PNAS...68..486K. doi:10.1073/pnas.68.2.486. PMC 388966. PMID 16591908.
6. Kite, GC; Cardoso, D; Lewis, GP; Zartman, CE; de Queiroz, LP; Veitch, NC (2015). "Monomethyl ethers of 4,5-dihydroxypipecolic acid from Petaladenium urceoliferum: Enigmatic chemistry of an enigmatic legume". Phytochemistry. 116: 198–202. Bibcode:2015PChem.116..198K. doi:10.1016/j.phytochem.2015.02.026. PMID 25817832.