Isoamyl alcohol (also known as isopentyl alcohol) is a clear, colorless alcohol with the formula (CH3)2CHCH2CH2OH. It is one of several isomers of amyl alcohol. It is a main ingredient in the production of banana oil, an ester found in nature and also produced as a flavouring in industry. It's also the main ingredient of Kovac's reagent, used for the bacterial diagnostic indole test.
It is also used as an antifoaming agent in the Chloroform:Isomyl Alcohol reagent.[3]
Isoamyl alcohol is used in a Phenol–chloroform extraction mixed with the chloroform to further inhibit RNase activity and prevent solubility of RNAs with long tracts of poly-adenine.[4]
It is one of the components of the aroma of Tuber melanosporum, the black truffle. It has been identified as a chemical in the pheromone used by hornets to attract other members of the hive to attack