Unexpected formation of a fused double cycle trinuclear gold(i) complex supported by ortho-phenyl metallated aryl-diphosphine ligands and strong aurophilic interactions.

The first homoleptic trinuclear arylgold(i) complex, [Au3(L')2](NO3) (3), based on an ortho-phenyl metallated aryl-diphosphine ligand (L' = o-C6H4PPh(C15H10O)PPh2), has been obtained through a new thermolytic reaction of the corresponding diauracycle, [Au2(L)2](NO3)2 (L = xantphos). The formation of 3 involves activation of the ortho-phenyl C-H bond of the xantphos ligands. The presence of Au-C bonds in this new gold-diphosphine cluster is not its only remarkable feature, since it also displays two 12-membered rings fused together and a linear {Au3} chain with aurophilic interactions.

Synthesis and Enantiomeric Recognition Studies of Optically Active Pyridino-Crown Ethers Containing an Anthracene Fluorophore Unit.

Novel enantiopure pyridino-18-crown-6 ether-based sensor molecules containing an anthracene fluorophore unit were synthesized. Their enantiomeric recognition abilities toward the enantiomers of 1-phenylethylamine hydrogen perchlorate (PhEt), 1-(1-naphthyl)ethylamine hydrogen perchlorate (NapEt), phenylglycine methyl ester hydrogen perchlorate (PhgOMe), and phenylalanine methyl ester hydrogen perchlorate (PheOMe) were examined in acetonitrile using fluorescence spectroscopy. The sensor molecules showed appreciable enantiomeric recognition toward the enantiomers of NapEt, PhEt, and PhgOMe.

Mechano-induced reversible colour and luminescence switching of a gold(i)-diphosphine complex.

A gold(i)-diphosphine simultaneously exhibits reversible mechanochromism and mechanochromic luminescence. The mechanical grinding can trigger a transformation from a neutral mononuclear structure exhibiting white colour and blue photoluminescence to an ionic dinuclear structure with intramolecular aurophilic interactions exhibiting yellow colour and red emission.

Anion-, Solvent-, Temperature-, and Mechano-Responsive Photoluminescence in Gold(I) Diphosphine-Based Dimers.

A series of [Au2 (nixantphos)2](X)2 (nixantphos=4,6-bis(diphenylphosphino)-phenoxazine; X=NO3, 1; CF3 COO, 2; CF3 SO3, 3; [Au(CN)2], 4; and BF4, 5) complexes that exhibit intriguing anion-switchable and stimuli-responsive luminescent photophysical properties have been synthesized and characterized. Depending on their anions, these complexes display yellow (3), orange (4 and 5), and red (1 and 2) emission colors. They exhibit reversible thermo-, mechano-, and vapochromic luminescence changes readily perceivable by the naked eye.

Mechanochemical synthesis of crystalline and amorphous digold(I) helicates exhibiting anion- and phase-switchable luminescence properties.

For the first time, mechanochemical synthesis has been used for the preparation of crystalline and amorphous dinuclear gold(i) helicates, [Au2L2](X)2 (L = xantphos; X = CF3SO3, SCN, BF4 and PF6), that show anion- and phase-switchable luminescence properties. This solid-state approach provides strategies for developing switchable luminescent materials.

Photodynamic effects of novel 5,15-diaryl-tetrapyrrole derivatives on human colon carcinoma cells.

Preliminary in vitro cytotoxicity studies on a panel of meso diaryl-substituted tetrapyrrole derivatives newly synthesized in our laboratory have shown that these compounds are photodynamically active on the human colon carcinoma cell line HCT116. In the present study, we investigate some mechanistic aspects of the photodynamic action of the most active compounds in the series, namely the 5-phenyl-15-(3-methoxyphenyl)porphyrin (1), the 5-phenyl-15-(3-hydroxyphenyl)porphyrin (2) and the 5,15-diphenylporphyrin (3). The results of the cytotoxicity studies indicate that the novel photosensitisers (PSs) are more potent in vitro than m-THPC (Foscan), a powerful PS already approved for clinical use in photodynamic therapy (PDT).

Absorption, fluorescence, and cd spectroscopic study of chiral recognition by a binaphthyl-derived chromogenic calixcrown host.

The (R)- and (S)-enantiomers of a binaphthyl-appended calix[4]crown-6 ether with two 2,4-dinitrophenylazo chromophore units ((R)-1 and (S)-1) as chiral hosts were tested in their reactions with the enantiomers of alpha-methylbenzylamine ((R)-MBA, (S)-MBA)) and phenylglycinol ((R)-PGL, (S)-PGL) as chiral guests. The visible absorption spectra indicate a two-step process: the first is a nonenantioselective proton transfer from the host to the guest, which is followed by the enantioselective real complexation. In the visible range of the CD spectra a positive/negative band belongs to the absorption of pure (R)-1/(S)-1, and a negative/positive exciton couplet to the absorption of (R)-1-(S)-MBA/(S)-1-(R)-MBA complexes.

Quenching of singlet oxygen (1deltag) by cobalt complexes with four nitrogen atoms in the equatorial plane.

The quenching of singlet oxygen (1deltag) by cobalt(III)-bis-1,2-benzosemiquinone-diiminato complexes (general structure LCo(111)(BQDI)2ClO4) has been studied in different solvents by measuring the singlet oxygen phosphorescence decay in time-resolved experiments. The axial ligand (Ph3As, Ph3Sb, N-methyl-imidazole, pyrrolidine) has practically no influence on the quenching; however, the chlorinated benzosemiquinone-diiminato complex has a markedly lower quenching rate constant. The solvent effects can be fully explained by the difference in viscosity, which supports the assumption that the quenching is diffusion controlled.

[Iron deficiency anemia caused by occult intestinal bleeding due to milk allergy (author's transl)].

With the passive hemagglutination method the authors proved antibodies against milkprotein fractions in three of nine patients with hypochrome anemia aged 7, 12 and 17 months. In these children the X-ray examination showed an intestinal allergy, presumably the reason for occult intestinal bleeding which inturn caused hypochrome anemia. After milk was eliminated from the diet iron therapy restored a normal haemoglobin content.

Activity alterations of metabolic enzymes in the anterior pituitary of female rats during acute and chronic starvation, as well as after refeeding.

The activity of glycolysis and hexose monophosphate shunt decreases while the activity of some oxydative enzymes and acid phosphatase increases in the anterior pituitary of adult female rats during starvation. The alterations depend on the severity of starvation. The polypeptide hormone production also decreases.

The role of estrogens in the regulation of lactate dehydrogenase activity and its submolecular organization in rat anterior pituitary.

Estrogens increase LDH activity and decrease H/M subunit ratio in rat anterior pituitary in both the experimental circumstances and the physiological conditions. The cellular messengers mediating estrogenic effect are structure- and stereospecific. The activity increasing and subunit ratio decreasing potency of the three tested estrogens was of following decreasing order: 17 beta-estradiol, estrone, and estriol.

Changes of lactic dehydrogenase activity and combination of its subunits in rat anterior pituitary during puberty and in maturity, as well as during estrous cycle on the actue effect of estradiol and after castration.

LDH activity in the female rat anterior pituitary increases substantially at the opening of the vagina, after the gradual increase up to the 90st day no important change occurs. During the estrous cycle activity reaches its peak during the estrus, and lowest in ghe proestrus. Molecular organization of the enzyme shows a change only at the opening of the vagina, i.

Sexual difference in pituitary pyruvic acid content, as well as of lactic acid/pyruvic acid quotient.

The lactic acid/pyruvic acid quotient of rat anterior pituitary varies betweeen 30 and 80. The dominance of lactic acid is in accordance with the earlier observation that pituitary lactate dehydrogenase isoenzymes in rat are made up, in majority, of M subunits. The pituitary lactic acid concentration in female and male animals shows no appreciable difference and does not change 2 and 4 weeks after castration.

Correlation between sexual steroid effect and activity changes and isoenzyme distribution of lactate dehydrogenase (EC 1.1.1.27) in rat anterior pituitary.

Sexual steroid feed-back is a fundamental regulating factor oification of pituitary metabolism in rat. Oestrogen synthesis and/or activity of M subunif testosterone, in males testosterone treatment as well as lack of oestrogen result in characteristic pituitary LDH activity and isoenzyme distribution. Physiological doses of sexual steroids affect, directly or indirectly, pituitary LDH activity, oxydative metabolism, and imply different biochemical bases for the polypeptide hormone production in the anterior pituitary gland.