Pararosanilin (or pararosaniline) is one of the major constituents of Basic fuchsin, together with Rosanilin and Magenta II. It is the component which makes the best Schiff's reagent, although samples of basic fuchsin can vary considerably in the proportion of the dye. Pararosanilin may be purchased under it's own name, and is more reliable for Shiff's reagent when this is done. Compare the formulae of the three constituents of basic fuchsin and the related dye, new fuchsin.