For years it was known that
Indigofera spicata was toxic to cows, rabbits and sheep. Both leaves and seeds are poisonous. Leaves were shown to contain
β-nitropropionic acid, which affected chickens, but it was not found in the seeds. M. P. Hegarty, and A. W. Pound performed experiments to isolate the toxin by examining its effect on mouse livers. They used absorption dialysis and
paper chromatography to separate chemical components from seeds, focusing on strong bases. Ninhydrin revealed where the different chemicals were on the paper used for chromatography. Bands were cut out of the paper, the substances extracted and then tested on the mice. Only one band was
hepatotoxic. The substance was crystallised as a hydrochoride. The hydrochloride melted between 131 and 134°C. (α) + 18°. The ratio of elements was established and a rough molecular weight. From the degradation products, the structure was determined. ==Properties==