Synthesis of 1-propargyl-1-(2-methyl-3-oxo-3-(p-tolyl)propyl)-piperidin-1-ium bromide and its plant growth-stimulating activity assessment

The aim of this study was to synthesize novel ionic compound – 1-propargyl-1-(2-methyl-3-oxo-3-(p-tolyl)propyl)-piperidin-1-ium bromide – via the N-alkylation (in conventional conditions and using ultrasound activation), and investigate its influence on the plant growth-stimulating activity using of sweet sorghum seeds. The synthesized compound was fully characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. Regardless of the type of synthesis’ methods, the isolated yield of the produced ionic compound is showed 79-81%, however, the reaction rate was significantly increased by using ultrasonic activation. For the assessment of the growth-stimulating activity of the synthesized ionic compound, parameters such as root length, shoot length, seed energy germination rate, and germination capacity were determined on 10 genotypes of sweet sorghum seeds. The results of samples with low concentration (0.001% vol. solution) were demonstrated the higher intensity for tested genotypes than control samples, especially for process of gemmogenesis and intensity of rhizogenesis. The results of this study can be used as basis for the further development of plant growth stimulants based on ionic compounds.