Wikipedia
Sec-Butylamine
sec-Butylamine is an organic chemical compound (specifically, an amine) with the formula CHCHCH(NH)CH, and occurs as a colorless liquid. sec-Butylamine is one of the four isomeric amines of butane, the others being n-butylamine, tert-butylamine and isobutylamine. It is very harmful to aquatic organisms.
sec-Butylamine is used as a fungicide and is considered a high production volume chemical. It is undergoing comprehensive review by the American Chemistry Council's Amines Panel as part of the Primary Amines Category.