Reactone dyes

Reactone dyes, which contain trichloropyrimidinyl groups, react with polysaccharides in an analogous way to chlorotriazinyl dyes, but the extent of reaction is somewhat less, at least in their reaction with cellulose. Reactone Red 2B derivatives of amylose, amylopectin, " starch, and barley )8-glucan provide substrates for amylases and y3-glucanases in the assay of these enzymes. 

Heterocyclic halogen-containing groups other than dichlorotriazinyl and chlorotriazinyl have been used in the preparation of reactive dyes. The Reactone and Drimarine colours are substitution products of tetrachloro-pyrimidine, (9), and therefore contain a trichloropyrimidyl group in the molecule, (10). An example of such a dyestuff is Reactone Red 2B, (11). 

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