pubmed-article:15586819 | pubmed:abstractText | The importance of six theoretically calculated molecular parameters in the antigibberellin (retardant) activity of quaternary ammonium salts is studied using regression analysis. A bioassay system based on cell culture of fungus Gibberella fujikuroi is used to determine the activity. In the case of N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium chloride (choline) and N,N,N-triethyl-N-(2-hydroxyethyl)ammonium chloride (N,N,N-triethylcholine) derivatives with linear structure, the polarizability, proton acceptor activity, and lipophilicity of these compounds exert the largest effect on the antigibberellin activity. The antigibberellin activity of more sterically hindered N,N-dialkylpiperidinium salts was mainly defined by the steric parameter, while the polarizability, proton acceptor activity, and (through them) lipophilicity exert a lesser effect. Other parameters are of minor importance for the three groups of compounds studied. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru. | lld:pubmed |