Light-induced electron-transfer reactions between chlorophyll a and hydrogenated pteridine derivatives in solution.

Preliminary studies of the formation of cationic 2 - amino - 6, 7 - dimethyl - 4 - hydroxy - 5, 6, 7, 8 - tetrahydropteridine radicals in alcoholic solution are reported. The results indicate that the same type of radical is formed either by oxidizing agents like hydrogen peroxide and iodine, or in a photoinduced reaction with chlorophyll a. A similarity between the epr signal of the light-induced cationic pteridine radical and the photoinduced epr signal II in photosynthesis is observed.