Quirks of dye nomenclature. 15. Geranine - a simple name, with a less than straight forward identity

摘要

Geranines were manufactured initially as textile dyes; they were made by coupling diazotized aromatic amines with sulfonated 1-naphthols. Most commonly encountered was geranine G, which for more than fifty years was thought to be derived from 1-naphthol monosulfonic acid, but later was considered to be derived from a 1-naphthol disulfonic acid. Currently, geranine G is thought to be a mixture of two isomers derived from 1-naphthol disulfonic acids. This species and others are described here by chemical structure and by other reference names and numbers where available. The occasional uses of geranines as biological stains are documented.