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Class: Thiazole
Ionisation: Acid

Chemical structure of Primuline
Chemical structure of Primuline

Common Name: Primuline
Suggested Name: Primuline
Other Names:

C.I. Number: 49000
C.I. Name: Direct yellow 59
Color: Yellow
Solubility Aqueous:
Solubility Ethanol:
Absorption Maximum: 356 (Aldrich)
Empirical Formula: C21H14N3O3S3Na
Formula Weight: 475.6


Primuline is a vital fluorescent dye and is used for that reason. It is rarely used for any other purpose.

According to the Color Index, primuline is composed predominantly of the dye with the formula on the top, along with some of the dye illustrated on the bottom.


  1. R. D. Lillie.
    Conn’s Biological Stains
    Williams & Wilkins, Baltimore, MD., U.S.A.
  2. Aldrich chemical catalogue, 1992
    Aldrich Chemical Company, Milwaukee, WI, USA.