Selective Pathway toward Heteroleptic Spin-Crossover Iron(II) Complexes with Pyridine-Based -Donor Ligands.

A new synthetic pathway is devised to selectively produce previously elusive heteroleptic iron(II) complexes of terpyridine and ,'-disubstituted bis(pyrazol-3-yl)pyridines that stabilize the opposite spin states of the metal ion. Such a combination of the ligands in a series of the heteroleptic complexes induces the spin-crossover (SCO) not experienced by the homoleptic complexes of these ligands or shifts it to lower/higher temperatures respective to the SCO-active homoleptic complex. The midpoint temperatures of the resulting SCO span from ca.

Multicomponent Molecular Systems Based on Porphyrins, 1,3,5-Triazine and Carboranes: Synthesis and Characterization.

2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride) is an excellent coupling reagent for the preparation of highly structured multifunctional molecules. Three component systems based on porphyrin, cyanuric chloride and carborane clusters were prepared by a one-pot stepwise amination of cyanuric chloride with 5-(4-aminophenyl)-10,15,20-triphenylporphyrin, followed by replacement of the remaining chlorine atoms with carborane - or -nucleophiles. Some variants of 1,3,5-triazine derivatives containing porphyrin, carborane and residues of biologically active compounds such as maleimide, glycine methyl ester as well as thioglycolic acid, mercaptoethanol and hexafluoroisopropanol were also prepared.

The Phosphonate Derivative of C Fullerene Induces Differentiation towards the Myogenic Lineage in Human Adipose-Derived Mesenchymal Stem Cells.

Inductors of myogenic stem cell differentiation attract attention, as they can be used to treat myodystrophies and post-traumatic injuries. Functionalization of fullerenes makes it possible to obtain water-soluble derivatives with targeted biochemical activity. This study examined the effects of the phosphonate C fullerene derivatives on the expression of myogenic transcription factors and myogenic differentiation of human mesenchymal stem cells (MSCs).

Anti-amyloid activities of three different types of water-soluble fullerene derivatives.

Anti-amyloid activity, aggregation behaviour, cytotoxicity and acute toxicity were investigated for three water-soluble fullerene derivatives with different types of solubilizing addends. All investigated compounds showed a strong anti-amyloid effect in vitrocaused by interaction of the water-soluble fullerene derivatives with the Ab(1-42)-peptide and followed by destruction of the amyloid fibrils. Notably, all of the studied fullerene derivatives showed very low cytotoxicity and low acute toxicity in mice (most promising compound 3 was more than four times less toxic than aspirin).

Synthesis of different types of alkoxy fullerene derivatives from chlorofullerene CCl.

We report novel synthetic routes for facile preparation of highly functionalized fullerene derivatives C(OR)X (X = H, Cl, Br), C(OR)O and C(OR) from chlorofullerene CCl. The first water-soluble fullerene compound bearing residues of 3-oxypropanoic acid demonstrated a potent anti-HIV activity.

A zeta potential value determines the aggregate's size of penta-substituted [60]fullerene derivatives in aqueous suspension whereas positive charge is required for toxicity against bacterial cells.

Background: The cause-effect relationships between physicochemical properties of amphiphilic [60]fullerene derivatives and their toxicity against bacterial cells have not yet been clarified. In this study, we report how the differences in the chemical structure of organic addends in 10 originally synthesized penta-substituted [60]fullerene derivatives modulate their zeta potential and aggregate's size in salt-free and salt-added aqueous suspensions as well as how these physicochemical characteristics affect the bioenergetics of freshwater Escherichia coli and marine Photobacterium phosphoreum bacteria. Dynamic light scattering, laser Doppler micro-electrophoresis, agarose gel electrophoresis, atomic force microscopy, and bioluminescence inhibition assay were used to characterize the fullerene aggregation behavior in aqueous solution and their interaction with the bacterial cell surface, following zeta potential changes and toxic effects.

Hybrid photoactive fullerene derivative-ruboxyl nanostructures for photodynamic therapy.

Here we report the investigation of photophysical properties and photodynamic action of two novel water soluble hybrid molecular structures based on [60]fullerene dyads bearing covalently attached residues of anthracycline antibiotic "ruboxyl". Molecular structures of the designed compounds were confirmed by IR and UV-VIS absorption spectroscopy, electrospray mass spectrometry (compound 5), and (1)H and (13)C NMR spectroscopy. Dynamic light scattering, steady-state and kinetic fluorimetry and UV-VIS absorption spectroscopy techniques were used to study the behavior of the synthesized hybrid molecular structures in aqueous solutions.

Arbuzov chemistry with chlorofullerene C60Cl6: a powerful method for selective synthesis of highly functionalized [60]fullerene derivatives.

We report Arbuzov-type reactions of chlorofullerene C(60)Cl(6) with trialkyl phosphites producing highly functionalized fullerene derivatives C(60)[P(O)(OR)(2)](5)H with high yields. The designed family of [60]fullerene phosphonic acids and their esters showed unusual properties which might find valuable material science applications.

Highly selective reactions of C60Cl6 with thiols for the synthesis of functionalized [60]fullerene derivatives.

Chlorofullerene C(60)Cl(6) undergoes highly selective reactions with thiols forming compounds C(60)[SR](5)H with high yields. These reactions open up straightforward synthetic routes to many functionalized fullerene derivatives, e.g.

Facile preparation of amine and amino acid adducts of [60]fullerene using chlorofullerene C60Cl6 as a precursor.

We report a general synthetic approach to the preparation of highly functionalized amine and amino acid derivatives of [60]fullerene starting from readily available chlorofullerene C(60)Cl(6). The synthesized water-soluble amino acid derivative of C(60) demonstrated pronounced antiviral activity, while the cationic amine-based compound showed strong antibacterial action in vitro.

The remarkable chemistry of trannulenes: green fluorinated fullerenes with unconventional aromaticity.

We report the first reaction of trannulenes involving their thermal isomerization to a new class of compounds termed "triumphenes". The thermodynamically controlled conversion of trannulenes into triumphenes is accompanied by an unprecedented migration of three organic addends from one hemisphere of the fullerene cage to another. The reaction products, bearing aliphatic substituents, might find applications in materials science as strong electron acceptors due to the presence of fifteen electron-withdrawing fluorine atoms in their molecular framework.

Self-assembly of thiophene- and furan-appended methanofullerenes with poly(3-hexylthiophene) in organic solar cells.

Novel fullerene derivatives bearing thiophene and furan residues were synthesized and studied as electron acceptor materials in bulk heterojunction organic solar cells, together with poly(3-hexylthiophene) (P3HT) as the donor polymer. Some compounds showed large nanomorphological inhomogenities in blends with P3HT; in particular, clusters with dimensions in the range of 100-1000 nm were formed. However, some blends that showed such large clusters yielded at the same time high power conversion efficiencies in photovoltaic devices, approaching 3.