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.

CAS：565-63-9
中文别名：2-甲基异巴豆酸;(Z)-2-甲基-2-丁烯酸;当归酸;
英文别名：(Z)-2-methyl-2-butenoic acid;cis-2-methylbutenoic acid;ANGELIC ACID;2-METHYLISOCROTONIC ACID;2-Butenoic acid, 2-methyl-, (Z)-;sumbulic acid;2-methyl-cis-crotonicacid;(Z)-MeCH=C(Me)COOH;trans-2-methyl-2-butenoic acid;cis-2-Methyl-2-butenoic acid;trans-2,3-dimethylacrylic acid;ANGELIC ACID(RG);
分子式：C5H8O2
分子量：100.116
精确质量：100.052
Psa：37.3
Logp：1.0372

UNII：54U4ZPB36F

外观与性状：淡黄色结晶固体
密度：1.01 g/cm3
沸点：198.5ºC at 760 mmHg
熔点：44ºC
闪点：95.9ºC
储存条件：Refrigerator

安全说明：S26; S36/37/39
危险类别码：R34
危险品运输编码：UN 3261
海关编码：2916190090
包装等级：II