Abstract: | The electronic absorption and circular dichroism (CD) spectra of ten natural and modified quinoid pigments are described. An assignment has been made of the dichroic absorption in the 250–600 nm region of the CD spectra of the pigments investigated. It has been shown that in the solution of stereochemical questions for such compounds the most informative region of the CD spectrum is the 250–350 nm interval.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 568–573, September–October, 1983. |