Prephenic acid

Names
Preferred IUPAC name (1s,4s)-1-(2-Carboxy-2-oxoethyl)-4-hydroxycyclohexa-2,5-diene-1-carboxylic acid
Other names Prephenate; cis-1-Carboxy-4-hydroxy-α-oxo-2,5-cyclohexadiene-1-propanoic acid
Identifiers
CAS Number	126-49-8 (unspecified) Y 87664-40-2 (cis) Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:84387 N
ChemSpider	16735981 Y
MeSH	Prephenic+acid
PubChem CID	1028 (unspecified)
UNII	Z66B98Z97I (unspecified) Y
CompTox Dashboard (EPA)	DTXSID60894109
InChI InChI=1S/C10H10O6/c11-6-1-3-10(4-2-6,9(15)16)5-7(12)8(13)14/h1-4,6,11H,5H2,(H,13,14)(H,15,16)/t6-,10+ Y Key: FPWMCUPFBRFMLH-XGAOUMNUSA-N Y InChI=1/C10H10O6/c11-6-1-3-10(4-2-6,9(15)16)5-7(12)8(13)14/h1-4,6,11H,5H2,(H,13,14)(H,15,16)/t6-,10+ Key: FPWMCUPFBRFMLH-XGAOUMNUBN
SMILES O=C(O)[C@@]/1(CC(=O)C(O)=O)\C=C/[C@@H](O)\C=C\1
Properties
Chemical formula	C10H10O6
Molar mass	226.184 g·mol−1
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

Prephenic acid, commonly also known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine, as well as of a large number of secondary metabolites of the shikimate pathway.

It is biosynthesized by a [3,3]-sigmatropic Claisen rearrangement of chorismate.^[1][2]

Stereochemistry

Prephenic acid is an example of achiral (optically inactive) molecule which has two pseudoasymmetric atoms (i.e. stereogenic but not chirotopic centers), the C1 and the C4 cyclohexadiene ring atoms. It has been shown^[3] that of the two possible diastereoisomers, the natural prephenic acid is one that has both substituents at higher priority (according to CIP rules) on the two pseudoasymmetric carbons, i.e. the carboxyl and the hydroxyl groups, in the cis configuration, or (1s,4s) according to the new IUPAC stereochemistry rules (2013).^[4]

The other stereoisomer, i.e. trans or, better, (1r,4r), is called epiprephenic.