Malachite green metabolized into LMG. Only the cation MG is deeply colored, whereas the leuco and alcohol derivatives are not. This difference arises because only the cationic form has extended pi-delocalization, which allows the molecule to absorb visible light. The leuco form of malachite green was first prepared by Hermann Fischer in 1877 by condensing benzaldehyde and dimethylaniline in the molecular ratio 1:2 in the presence of sulfuric acid. Malachite green is traditionally used as a dye. Kilotonnes of MG and related triarylmethane dyes are produced annually for this purpose. MG is active against the oomycete "Saprolegnia", which infects fish eggs in
The Malachite Casket (fairy tale) forgets about his mistress. He buys the Casket from her and offers it to Tanyushka, but she refuses. Turchaninov then claims that he wishes to marry the girl. She announces that she will only agree to the marriage if he shows her the Tsarina herself at the Malachite Room in Saint Petersburg. Turchaninov agrees. Dressed like a queen, Tanyushka arrives at the Palace, and walks directly to the Malachite Room. Tsarina enters the room, saying: "Now then, show me this nigh-handed maid". Upon hearing that Tanyushka frowns and says to Turchaninov: "What does this mean? I told ye to show