Tyrindoxyl sulfate

Tyrindoxyl sulfate (212) was originally isolated from the gastropod Mur ex truncatus and has been used as a source of the dye Tyrian purple since antiquity. It has also been identified in several other species of marine molluscs [2]. 

On the other hand, the almost colorless fluid secreted by Murex brandaris, a shellfish of the Mediterranean Sea region, becomes reddish purple on contact with air. The fluid was used by the Phoenicians as a dye from about 1500 BC, and the purple dye is known as Tyrian purple, ancient purple, or shellfish purple, etc. Friedlander, in 1915, isolated about 1.5 g of the pigment from 12,000 specimens of M. brandaris, and clarified its chemical structure as 6,6 -dibromoindigo [5]. Subsequently, the origin of this pigment was identified as sodium tyrindoxyl sulfate [6]. 

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