[Untitled]

In recent years, considerable effort of researchers has been devoted to studying the cellular signal systems, that is, the pathways of information transfer inside the cell. A significant role in this process is played by the transport of K, Na, Ca, Mg and some other ions. In connection with this, it is interesting to study ionophores – compounds with a special molecular structure that renders them capable of carrying small ions through lipid barriers. Ionophores are stable both chemically and biologically. These compounds either contain macrocyclic structural fragments or are capable of forming such structures by means of hydrogen bonds. Macrocyclic ionophores of natural origin can be considered as prototypes of crown compounds [1]. As is known, actinomycin D forms complexes with Na analogous to those formed by crown compounds [2, 3]. The crown groups can be introduced into the structure of a DNA complexon [4], but the effect of such groups upon the antitumor activity of such complexes has not been systematically studied. It was suggested that the complexation of actinomycin D with Na is related to the properties of cyclopeptide groups of this antibiotic, which are composed predominantly of N-alkylamino acids [5, 6]. We suggested that introducing crown groups free of cationoid centers into the amide groups of actinocin amides would lead to new compounds with properties close to those of actinomycin D. In this context, we have synthesized actinocin derivatives containing benzo-15-crown-5 and benzo-18-crown-6 groups attached via amide bonds. We studied both compounds with the crown fragments introduced immediately in the amide groups of actinocin diamides [7] and those in which with the fragments were separated from the amide groups by amino acid residues (glycine, -alanine, and 6-aminocaproic acid) [8]. The compounds studied were synthesized as described previously [7, 8].