A2:1 β-cyclodextrin – histochrome complex was synthesized based on a comparison with experimental studies of histochrome and showed antioxidant activity prolonged to 16 d as compared with 6 d for histochrome in tests of the duration of the in vitro antioxidant effect. PMR measurements proved that a β-cyclodextrin – histochrome complex formed. Computer modeling of the β-cyclodextrin–histochrome complex showed that the head-to-tail complex corresponded to the energy minimum.