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Structural formula
Structure of parafuchsin
Surname Parafuchsin
other names
  • Pararosaniline
  • 4,4 '- (4-iminocyclohexa-2,5-dienylidenemethylene) dianiline
  • CI Basic Red 9
Molecular formula C 19 H 17 N 3
Brief description

greenish solid

External identifiers / databases
CAS number
  • 479-73-2 (parafuchsin)
  • 569-61-9 (hydrochloride)
EC number 610-397-8
ECHA InfoCard 100.106.992
PubChem 11293
ChemSpider 10819
Wikidata Q421256
Molar mass 323.82 g mol −1
Physical state


Melting point

268–270 ° C (decomposition)


10 g l −1 (25 ° C, hydrochloride)

safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary
08 - Dangerous to health


H and P phrases H: 350
P: 201-308 + 313
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Parafuchsin is a chemical compound . It occurs in the commercially available, red triphenylmethane dye fuchsin , which is dissolved in ethanol and used for staining in microscopy and histology . Parafuchsin and Fuchsin differ in a methyl group and are therefore homologous .

Extraction and presentation

Parafuchsin is created when fuchsin is represented as an impurity. Fuchsine is produced by reacting 4-aminobenzaldehyde , 4-aminobenzyl alcohol or 4,4'-diaminodiphenylmethane with aniline in the presence of oxidizing agents and iron (II) chloride .


The molecule is a mesomeric stabilized cation with the properties of a cyanine dye . This is the reason for the intense color of the commercially available fuchsin (contaminated with parafuchsin). Alcoholic fuchsin solutions have an abnormal dispersion .

The parafuchsin's hydrochloride is mesomeric stabilized, from which an intense color is derived.

Mesomerism of parafuchsin hydrochloride

Web links

Commons : Parafuchsin  - Collection of images, videos and audio files

Individual evidence

  1. a b c Data sheet pararosaniline (chloride) (PDF) from Merck , accessed on December 30, 2019.
  2. a b Entry on parafuchsin in the GESTIS substance database of the IFA , accessed on December 30, 2019(JavaScript required) .
  3. Entry on 4,4 '- (4-iminocyclohexa-2,5-dienylidenemethylene) dianiline hydrochloride Template: link text check / apostrophe in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 30, 2019. Manufacturers or distributors can use the harmonized classification and labeling expand .
  4. External identifiers or database links for parafuchsin hydrochloride : CAS number: 569-61-9, EC number: 209-321-2, ECHA InfoCard: 100.008.475 , GESTIS substance database : 105310 , PubChem : 11292 , ChemSpider : 10818 , Wikidata : Q27890208 .