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Abstract: Series of phthalocyanines of zirconium containing lysine, citric, nonanoic acid residues and dibenzolylmethane groups as out-of-plane ligands are firstly studied as inhibitors of fibrillogenesis using cyanine-based fluorescent inhibitory assay. It was shown that studied phthalocyanines at concentration of 20μM inhibited aggregation reaction on 38.5–57.6% and inhibitory activity of phthalocyanines depended on the chemical nature of out-of-plane ligand. For the most active compound PcZrLys2 (zirconium phthalocyanine containing lysine fragment) the efficient inhibitor concentration was estimated to be 37μM. AFM studies have shown that in the presence of PcZrLys2 the inhibition of fibrils formation and formation of spherical oligomeric aggregates took place. Due to the ability of phthalocyanines to decrease efficiently protein aggregation into the amyloid fibrils, modification of phthalocyanine molecules via out-of-plane substitutions was proposed as approach for design of anti-fibrillogenic agents with required properties. [Copyright &y& Elsevier]

Heterofunctionalized macrobicyclic precursors of cage complexes with a reporter group were prepared using a stepwise substitution of the iron(II) dichloroclathrochelate. • New heterodifunctionalized iron(II) clathrochelates were obtained. • They were prepared using one-pot stepwise synthetic procedure. • Their molecules contain the terminal biorelevant carboxyl and reactive C≡C groups. • They seem to be the precursors of clathrochelates with a reporter group. The heterodifunctionalized iron(II) clathrochelates, the molecules of which contain the terminal biorelevant carboxyl and reactive triple C≡C groups were obtained using the two-step synthetic procedures by a subsequent substitution of their dichloroclathrochelate precursor with para -carboxyphenylthiolate anion and 2-propargylamine. The complexes obtained were characterized using elemental analysis, HR-APPI and MALDI-TOF mass spectrometries, UV–Vis, 1H, 13C{1H}, 11B and 19F NMR spectroscopies, and by the single crystal X-ray diffraction for an iron(II) monochloroclathrochelate with terminal propargylamine group. Its FeN 6 -coordination polyhedron possesses a distorted trigonal prismatic – trigonal-antiprismatic geometry with the average distortion angle φ of approximately 26.1°. Fe–N distances in this monoribbed-functionalized molecule vary in a narrow range from 1.883(3) to 1.901(4) Å and the height h of the above polyhedron is equal to 2.30 Å. Cyclic voltammograms study of these complexes contain the single cathodic wave assigned to the metal-centered processes of the cathodic Fe2+/+ reduction and anodic Fe+/2+ re-oxidation, thus suggesting their quasi-reversible character. Chemical reactions (including a complete decomposition and a reductive hydrodehalogenation of the macrobicyclic molecules) of the propargylamine and propargylamide iron(II) clathrochelates was studied in various media and under the different experimental conditions using TLC, high-resolution APPI mass, NMR and UV–vis spectra, suggesting a complete slow destruction of the macrobicyclic frameworks of their molecules in aqueous solutions (including those modeling the physiological conditions). [ABSTRACT FROM AUTHOR]