Rubiadin

Description

Yellow plate-like crystals. Rubiadin is one of the natural dyes extracted from madder roots and other Rubiaceae family plants. It dissolves in alkalis to form a red solution and turns yellow in acids.

Synonyms and Related Terms

1,3-hydroxy-2-methylanthraquinone; CI 75350; rubiadina (Port.)

Risks

• Millipore Sigma: SDS

Physical and Chemical Properties

• Soluble in ethanol, ether, benzene. Insoluble in boiling water, lime water.
• Absorption max = 246, 280, 415 nm.

Composition	C15H10O4
Melting Point	302 C
Molecular Weight	mol. wt. = 254.24

Resources and Citations

• Artists' Pigments: A Handbook of their History and Characteristics, Elisabeth West FitzHugh, Oxford University Press, Oxford, Vol. 3, 1997 Comment: H.Schweppe, J.Winter, "Madder and Alizarin"