Perhydropyrimidinylium and 1,3-diazepinylium salts as potential ionic liquids

Saturated or partially saturated heterocyclic compounds were uncovered as interesting and potential ionic liquid media. Zwitterionic compounds with perhydropyrimidinylium, 1,3- diazepinylium and quinazolinylium carbocations were utilized in the preparation of a variety of salts in order to search for new low-melting ionic media. Some of the zwitterionic quinazoline derivatives were also found to be low-melting glasses

A water-soluble [60]fullerene-derivative stimulates chlorophyll accumulation and has no toxic effect on Chlamydomonas reinhardtii

Chlamydomonas reinhardtii (WT 2137) P. A. Dang. (Volvocales, Chlorophyceae) is a green microalgae serving as a suitable model in scientific research and a promising industrial biotechnology platform for production of biofuel, hydrogen and recombinant proteins. Fullerenes (C60) are allotropic carbon nanoparticles discovered in 1985 and used in biomedical studies since the early 1990s, when water solubilization methodologies were developed. Recently, surface-modified hydroxylated derivatives of fullerenes were proven to enhance algal growth and drought tolerance in plants. Here, a novel type of water-soluble [60]fullerene derivative with 12 glycine residues (GF) has been synthesized and tested for acute toxicity (up to 50 μg/ml) and as a potential biostimulant of algal growth. The effects of GF on pigment composition and growth rate of Chlamydomonas reinhardtii were systematically investigated. Our results suggest that GF was not toxic, and no negative change in the pigment content and no stress symptoms were observed. No changes in the photosynthetic parameters based on the fluorescence of chlorophyll a in Photosystem II (NPQ, Fv/Fm, Fv/F0, PI and RC/ABS) were observed. The GF had no effect on cell size and growth rate. At a concentration of 20 μg/ml, GF stimulated chlorophyll accumulation in 3-day-old cultures

New organic-inorganic hybrid compounds based on sodium peroxidomolybdates (VI) and derivatives of pyridine acids : structure determination and catalytic properties

Two organic-inorganic hybrids based on sodium peroxidomolybdates(VI) and 3,5-dicarboxylic pyridine acid (Na-35dcpa) or N-oxide isonicotinic acid (Na-isoO) have been synthesized and characterized. All compounds contain inorganic parts: a pentagonal bipyramid with molybdenum center, and an organic part containing 3,5-dicarboxylic pyridine acid or N-oxide isonicotinic acid moieties. The type of organic part used in the synthesis influences the crystal structure of obtained compounds. This aspect can be interesting for crystal engineering. Crystal structures were determined using powder X-ray diffraction or single crystal diffraction for compounds Na-35dcpa and Na-isoO, respectively. Elemental analysis was used to check the purity of the obtained compounds, while X-ray Powder Diffraction (XRPD) vs. temp. was applied to verify their stability. Moreover, all the compounds were examined by Infrared (IR) spectroscopy. Their catalytic activity was tested in the Baeyer–Villiger (BV) oxidation of cyclohexanone to ε-caprolactone in the oxygen-aldehyde system. The highest catalytic activity in the BV oxidation was observed for Na-35dcpa. The compounds were also tested for biological activity on human normal cells (fibroblasts) and colon cancer cell lines (HT-29, LoVo, SW 620, HCT 116). All compounds were cytotoxic against tumor cells with metastatic characteristics, which makes them interesting and promising candidates for further investigations of specific anticancer mechanisms

A [60]fullerene nanoconjugate with gemcitabine : synthesis, biophysical properties and biological evaluation for treating pancreatic cancer

Background:The first‑line chemotherapy drug that is used to treat pancreatic ductal adenocarcinoma is gemcitabine. Unfortunately, its effectiveness is hampered by its chemo‑resistance, low vascularization and drug biodistribution limitations in the tumor microenvironment. Novel nanotherapeutics must be developed in order to improve the prognosis for patients with pancreatic cancer.Results:We developed a synthetic methodology for obtaining a water‑soluble nano‑conjugate of a [60]fullerene‑glycine derivative with the FDA‑approved drug gemcit‑abine (nanoC60GEM). The proposed synthetic protocol enables a highly water‑soluble [60]fullerene‑glycine derivative (6) to be obtained, which was next successfully conju‑gated with gemcitabine using the EDCI/NHS carbodiimide protocol. The desired nano‑conjugate was characterized using mass spectrometry and DLS, IR and XPS techniques. The photogeneration of singlet oxygen and the superoxide anion radical were studied by measuring 1O2 near‑infrared luminescence at 1270 nm, followed by spin trapping of the DMPO adducts by EPR spectroscopy. The biological assays that were performed indicate that there is an inhibition of the cell cycle in the S phase and the induction of apoptosis by nanoC60GEM.Conclusion:In this paper, we present a robust approach for synthesizing a highly water‑soluble [60]fullerene nanoconjugate with gemcitabine. The performed biological assays on pancreatic cancer cell lines demonstrated cytotoxic effects of nanoC60GEM, which were enhanced by the generation of reactive oxygen species after blue LED irradiation of synthesized fullerene nanomaterial