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
Italian submarine Malachite of operations, she was attacked by an aircraft but the attack was beaten back with her anti-aircraft weapons. During the night January 27 1941 she patrolled in the Strait of Messina. From 9 to 18 February 1941 "Malachite" patrolled off Bardia. On February 14 she attempted an attack on an unidentified warship, but fails to launch torpedoes due to the high speed of the target. From 15 to 22 March 1941 she was deployed in the Kythira Strait. On the night of March 19, "Malachite" sighted a cruiser escorted by several destroyers. At 01:19 she launched two torpedoes but they