A

David

Darling

indigo

molecule of indigo

Indigo, also called indogitin (C16H10O2N2), is a violet-blue dye obtained from leguminous plants of the genus Indigofera. Indigo is produced by natural acidation of a solution containing pieces of the plants. Cultivation of indigo plants was once carried out on a large scale in India, but cheap synthetic indigo (available since the early 1900s) is now mainly used. Indigo was first synthesized by the German chemist Adolph von Baeyer.