Angelic acid

Angelic acid
Names
	Preferred IUPAC name (2Z)-2-Methylbut-2-enoic acid
	Other names (Z)-2-Methylbut-2-enoic acid
Identifiers
CAS Number	565-63-9 ;
3D model (JSmol)	Interactive image; Interactive image;
ChEBI	CHEBI:36431 ;
ChEMBL	ChEMBL55941 ;
ChemSpider	559009 ;
ECHA InfoCard	100.008.441
PubChem CID	643915;
UNII	54U4ZPB36F ;
CompTox Dashboard (EPA)	DTXSID80897430 ;
	InChI InChI=1S/C5H8O2/c1-3-4(2)5(6)7/h3H,1-2H3,(H,6,7)/b4-3- Key: UIERETOOQGIECD-ARJAWSKDSA-N ;
	SMILES C/C=C(C)\C(O)=O; O=C(O)\C(=C/C)C;
Properties
Chemical formula	C5H8O2
Molar mass	100.117 g·mol−1
Melting point	45.5 °C (113.9 °F; 318.6 K)
Boiling point	185 °C (365 °F; 458 K)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Angelic acid is a monocarboxylic unsaturated organic acid, mostly found in the plants of the family Apiaceae. It is a volatile solid with a biting taste and pungent sour odor. It is the cis isomer of 2-methyl-2-butenoic acid, which easily converts to the trans isomer, tiglic acid, upon heating or reaction with inorganic acids. The reverse transformation occurs much less readily. The salts and esters of angelic acid are called angelates. Angelic acid esters are the active components of herbal medicine used against a wide range of various health disturbances including pains, fever, gout, heartburn, etc.