Еcotoxicological evaluation of two new polyheterocyclic compounds was spending. Acute toxicity of test substances, their lethal and safe concentration (LC and BC) were determined. The nature of the biological effect of these compounds on the plants was investigated. The substances were stimulants during the germination of seeds of wheat and peas and inhibitors of the growth of the roots and stems of seedlings. It was determined the effect of various concentrations of tested compounds on the growth characteristics of plants.