Wiktionary
isobutyric acid
n. (context fatty acid English) 2-methyl-propanoic acid, (CH3)2CHCOOH, an isomer of butyric acid, that occurs in carob beans and croton oil.
Wikipedia
Isobutyric acid
Isobutyric acid, also known as 2-methylpropanoic acid, is a carboxylic acid with structural formula ( C H)-CH- COOH.
It is found in the free state in carobs ( Ceratonia siliqua), in vanilla and in the root of Arnica dulcis, and as an ethyl ester in croton oil.
Isobutyric acid is an isomer of n- butyric acid; they have the same chemical formula C H O but a different structure.