Ashworth P
Biochem J. 1974 Aug;141(2):577-80. doi: 10.1042/bj1410577.
The formation of diazodiphenoquinone pigments during bacterial oxidations of pyridinediols can be accounted for in terms of a free-radical mechanism similar to that operating for oxidations in vitro involving azasemiquinone radicals. Electron-spin-resonance spectra are of great value in pigment structure determinations.