Bismarck brown Y
Bismarck brown Y also called C.I. 21000 and C.I. Basic Brown 1, is a diazo dye with the idealized formula [(H2N)2C6H3N2]2C6H4. The dye is a mixture of closely related compounds. It was one of the earliest azo dyes, being described in 1863 by German chemist Carl Alexander von Martius. Martius named the dye after German chancellor Otto von Bismarck. It is used in histology for staining tissues.
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