ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Correlations between Structure and Biological Activity of Bis-Quaternary Isosters of 1,5-Pentanediammonium Dibromides Algicidal Activity and Inhibition of Photochemical Activity of Chloroplasts

K. Kráľová, D. Loos, F. Devínsky, and I. Lacko

Institute of Chemistry, Faculty of Natural Sciences, Comenius University, SK-842 15 Bratislava

Abstract: Isosteric N,N'-bis(alkyldimethyl)-3-X-1,5-pentanediammonium dibromides (PDDBr) (alkyl = n-hexyl-n-octadecyl) with X = CH₂, NCH₃, O or S inhibit photosynthetic processes in Chlorella vulgaris algae and in spinach chloroplasts. The dependence of the inhibitory activity against photosynthesizing organisms on the critical micelle concentration as well as on the number of carbon atoms in the alkyl substituents of PDDBr shows a nonlinear parabolic course. From two theoretical models (parabolic and bilinear) used for the description of correlations between biological activity and the structure of PDDBr the bilinear model gave better parameters of statistical analysis. The isosteric exchange of X = CH₂ to NCH₃, O or S practically did not affect the biological activity of PDDBr and the studied correlations could be expressed by a single regression equation for ail 36 investigated compounds.

Full paper in Portable Document Format: 491a39.pdf

Chemical Papers 49 (1) 39–42 (1995)