Relationships between structure, retention and biological activity of some Schiff base ligands and their complexes

Abstract

The lipophilicity of a series of Schiff base ligands and their complexes with nickel(II) and copper(II) has been determined by reversed-phase thin-layer chromatography using binary dioxane-water mobile phase. Chelate ligands were prepared by condensation of diamine and the corresponding beta-diketone. Copper(II) and nickel(II) complexes with chelate ligands containing ethane-1,2-diamine or propane-1,2-diamine as the amine part and pentane-2,4-dione and/or 1-phenylbutane-1,3-dione, pentane-2,4-dione and/or 1,1,1-trifluoropentane-2,4-dione, or 1,1,1-trifluoropentane-2,4-dione and/or 1-phenylbutane-1,3-dione as the beta-diketone part were synthesized. Some of investigated compounds were screened for their in vitro antifungal activity against Sacharomyces cerevisiae and antibacterial activity against Escherichia coli. Chromatographically obtained lipophilicity parameters were correlated both with calculated n-octanol-water partition coefficient C log P and antimicrobial activities. Satisfactory correlations were obtained. Chromatographic data proved to be reliable parameters for describing the lipophilic properties of the investigated compounds. Additionally, the principal components analysis was performed on the data chromatographically obtained. This statistical method was useful for distinguishing compounds and objective comparison of their lipophilicity parameters.

Research on a novel poly (vinyl alcohol)/lysine/vanillin wound dressing: Biocompatibility, bioactivity and antimicrobial activity

“…Compared with bacteria, it was found that the antibacterial activity toward E. coli was better than that of S. aureus. In virtue of the high level of lipopolysaccharide (LPS) in outer membrane of gram-negative bacteria, lipid-soluble materials [44] were more likely to pass the membrane than that of grampositive bacteria [45]. It might result in the passage of Schiff base through the cytoderm and the regression of permeability barrier capability of the membrane [46] because of the charge transfer behavior between the LPS molecules and the Schiff base molecule.…”

Correlation between structure, retention and activity of cholic acid derived cis–trans isomeric bis‐steroidal tetraoxanes

“…Since the tertiary amides (11)(12)(13)(14) do not possess any of proton donating abilities, they are placed at the opposite end of the PC1 axis. The only exception is a pair of methyl esters (1,2) which possesses only proton-accepting properties and is placed in the middle of the PC score graph. As it can be observed from Fig.…”

“…The same assumption that structure descriptors of substances are correlated with their properties and biological activity is widely used in quantitative structure-activity relationship (QSAR) studies. Because it is considered that the same basic intermolecular interactions determine the behaviour of substance in both biological and chromatographic environment [1], a similar influence of particular structural descriptors on both the retention and biological activity might be expected.…”

Effect of substituents on prediction of TLC retention of tetra‐dentate Schiff bases and their Copper(II) and Nickel(II) complexes

“…The retention and lipophilicity of these compounds were investigated on several thin layers. The quantitative relation between structure, retention and activity/property as well as electrochemical behavior and antioxidative activity of these compounds were also investigated (Aburas et al, ; Baošić & Tešić, ; Baošić, Milojković‐Opsenica, & Tešić, ; Baošić et al, ; Baošić, Radojević, Tripković, Aburas, & Tešić, ). The results motivated us to examine the effect of structure of Schiff bases and their Ni(II) and Cu(II) complexes on chromatographic behavior under normal‐ and reverse‐phase conditions in order to determine effect of substituent on retention.…”