ИСТИНА

To date, synthetic non-proteinogenic (or unnatural) complex amino acids (AAs) have a considerable interest in biochemistry and pharmaceutical industry. They are very often used in the development of new drugs and modified peptides. In most cases, such molecules can only be obtained using radical coupling reactions. The attractiveness of the approach is provided by the generation of radicals under mild conditions and the functional group tolerance. Recently, we have developed several reliable and practically useful protocols for the asymmetric synthesis of hard-to-reach amino acids through classical ionic and radical intermediates. Using of Belokon's chiral nickel(II) complex we could synthesize several important classes of AAs, some of which were produced for the first time (Scheme). In particular, enantiomerically pure unnatural α-AAs with γ-tertiary and quaternary carbon centers, alkyl and perfluoroalkylated α-AAs and cysteine derivatives have been obtained.