Literature References: Family of highly colored 2,3-dihydroindole-5,6-quinones obtained by oxidative cyclization of catecholamines: Sobotka, Austin, J. Am. Chem. Soc. 73, 3077 (1951). Best represented by a zwitterionic structure with the substituents determined by the catecholamine used, e.g. for epinephrine as starting material, R = CH3, R¢ = H, and R¢¢ = OH. Numerous physiological activities, such as hallucinogenic, hemostatic, radioprotective, have been ascribed to aminochromes. Reviews: Sobotka et al., Fortschr. Chem. Org. Naturst. 14, 217 (1957); Heacock, Adv. Heterocycl. Chem. 5, 205 (1965); Heacock, Powell, Prog. Med. Chem. 9, 275 (1972). Review of toxicity: A. Bindoli et al., Toxicol. Lett. 48, 3-20 (1989).
NOTE: See also adrenochrome, adrenolutin, carbazochrome salicylate.