In our days the name Fyodor Levin seems ordinary and unremarkable, and the name of Phoebus Theodore Aaron Leuven is known only to people interested in biochemistry, and mostly in the West and in the USA. However, both of these names belong to the one person, a great biochemist, a graduate of the Imperial Military Medical Academy, the largest researcher of nucleic acids and carbohydrates. With a great sense of purpose and the will to learn, F. Levin, despite forced emigration, the disease of tuberculosis and 20 years of unsuccessful experiments, made outstanding discoveries. With 7 nominations, he was never awarded the Nobel Prize, but it was his research that formed the basis for further work by E. Chargaff, D. Watson and F. Crick. The article explore the life and career of F. A. Levin in Russia and in the United States, his main discoveries and cooperation with Russian scientists (5 figs, bibliography: 12 refs).