Pararosaniline, Basic Red 9, or C.I. 42500 is an organic compound with the formula [(H2NC6H4)3C]Cl. It is a magenta solid with a variety of uses as a dye.[1] It is one of the four components of basic fuchsine.
It is used to dye polyacrylonitrile fibers. Pararosaniline is used as a colorimetric test for aldehydes, in the Schiff test. It is the only basic fuchsine component suitable for making the aldehyde-fuchsine stain for pancreatic islet beta cells.
Pararosaniline is a hydrochloride that is the monohydrochloride of 4,4'-[(4-iminocyclohexa-2,5-dien-1-ylidene)methanediyl]dianiline. One of the major constituents of Basic fuchsin, together with rosanilin, magenta II and new fuchsin. It has a role as a histological dye and a fluorochrome.
