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 Y
3D model (Jmol)	Interactive image Interactive image
ChEBI	CHEBI:36431 Y
ChemSpider	559009 Y
ECHA InfoCard	100.008.441
PubChem CID	643915
InChI InChI=1S/C5H8O2/c1-3-4(2)5(6)7/h3H,1-2H3,(H,6,7)/b4-3- Y Key: UIERETOOQGIECD-ARJAWSKDSA-N Y
SMILES C/C=C(C)\C(O)=O O=C(O)\C(=C/C)C
Properties
Chemical formula	C5H8O2
Molar mass	100.12 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).
Y  (what is YN ?)
Infobox references

Angelic acid is a monocarboxylic unsaturated organic acid. It is mostly found in the plants of the family Apiaceae. German pharmacist Ludwig Andreas Buchner isolated angelic acid in 1842 from the roots of garden angelica (Angelica archangelica) which gave the acid its name. Angelic acid 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.

Angelic acid was first isolated by the German pharmacist Ludwig Andreas Buchner (1813–1897) in 1842 from the roots of the garden plant angelica (Angelica archangelica) that gave the acid its name.

Angelic acid occurs in the roots of many plants, especially of the family Apiaceae. These plants include Angelica archangelica, Peucedanum ostruthium (masterwort), Levisticum officinale (lovage),Euryangium sumbul and Laserpitium latifolium. In the latter plant, it is present in the resin called laserpicium, and the oil of carrot also contains angelic acid. Sumbul plants might contain not angelic acid itself, but a larger complex which breaks into angelic acid upon processing. The acid can also be extracted from the oil of chamomile flowers, and 85% of Roman chamomile (Anthemis nobilis) oil consists of esters of angelic and tiglic acids; it also contains isobutyl angelate and amyl angelate. The acid content is highest in Angelica archangelica where it is about 0.3%.