[Cytogenetic analysis of the action of new bifunctional alkylating compounds].

The mutagenic activity of nitrogen mustard derivatives of aminovinylketones (NP-130, NP-161, NP-163), aminovinylphosphoric acid (RVS-445, RVS-446, RVS-448, RVS-398) and ethylene imine derivatives of ethane sulphonic acid (AR, RJ) was established for the first time in the experiments with Allium fistulosum L. The mutagenic activity of aminovinylketones (NP-130, NP-160) was established for the first time in the experiments with Crepis capillaris (L.) Wallr. The effect of the compounds studied on the seedlings characterized by the high level of natural mutability of chromosomes did not alter the spectrum of structural chromosome mutations. As it is shown by the results of the analysis, the compounds studied exert their action mainly at the S stage of the cell cycle. However, the initiation of potential changes at the G1 stage that are realized into actual breaks at the S stage is not excluded. In some experiments in which high concentrations of mutagens were used no delayed effect was observed which might be explained by the action of mutagens on cells at the G2 stage or at a still later stage.