Synthesis of novel diselenide-linked porphyrin dimers under phase-transfer catalysis condition and their interactions with DNA.

Novel diselenide-linked porphyrin dimers were synthesized under phase-transfer catalysis conditions. The targeted compounds were characterized by (1)H-NMR, high-resolution mass spectrometry, UV/VIS and fluorescence spectroscopies, redox-potential measurements, and elemental analysis. The interaction of the title compounds with DNA was studied using UV/VIS, fluorescence, and circular dichroism (CD) spectroscopies. The relative rates of singlet-oxygen production from the diselenide-linked porphyrin dimers upon photoirradiation were also measured.

Study of antibacterial activity of ZnZnbisporphyrin complexes and its free components on Staphylococcus aureus by microcalorimetry.

The antibacterial effect of Zn(II), tetraphenyl porphyrin (TPP), propdioxyl bridged tetraphenyl bisporphyrin 1, and its metallobisporphyrin complexes (ZnMnbisporphyrin 2 and ZnZnbisporphyrin 3) towards Staphylococcus aureus growth was investigated by microcalorimetry at 37 degrees C. Differences in their capacities to inhibit the growth metabolism of S. aureus were observed. By analyzing the power-time curves, crucial parameters such as the rate constant of bacterial growth (k), inhibitory ratio (I), and generation time (t (G)) were determined. The growth rate constant (k) of S. aureus (in the log phase) in the presence of the drugs decreased linearly with increasing concentrations of the complexes. The sequence of the antibacterial activities of these compounds tested was 3 > 2 > 1 > Zn(II) > TPP. ZnZnbisporphyrin 3 is proposed to benefit from the synergetic effects of Zn(II) and 1.

Antibacterial activities of novel diselenide-bridged bis(porphyrin)s on Staphylococcus aureus investigated by microcalorimetry.

The actions of two novel diselenide-bridged bis(porphyrin)s (1 and 2) on Staphylococcus aureus growth was investigated by microcalorimetry at 37.00 degrees C, compared with that of Na2SeO3. Differences in their capacities to inhibit the growth metabolism of S. aureus were observed. By analyzing the power-time curves, crucial parameters such as the rate constant of bacterial growth (k), inhibitory rate (I), and generation time (tG) were determined. The growth rate constant (k) of S. aureus (in the log phase) in the presence of the drugs decreased with increasing concentrations of the drugs regularly. The relationship of k and c is nearly linear for diselenide-bridged bis(porphyrin) 2. The sequence of the antibacterial activities of these selenium compounds tested was 2 > 1 > Na2SeO3.

Microcalorimetric and spectroscopic investigation of the antibacterial properties of cationic ytterbium(III)-porphyrin complexes lacking charged peripheral groups.

The antibacterial activities towards Escherichia coli of two cationic Yb(III)-monoporphyrin complexes, [Yb(III)(TMP)(H2O)3]Cl (1) and [Yb(III)(TTP)(H2O)3]Cl (2), were investigated at the cellular and sub-cellular levels. The biological effects of the complexes on the growth of E. coli were evaluated by microcalorimetry and by analysis of the resulting metabolic thermogenic curves, from which IC50 values and metabolic parameters such as growth rate and generation time were derived. At the subcellular level, DNA-binding experiments were performed by means of UV/VIS- and fluorescence-titration experiments, as well as by near-infrared (NIR) emission, which revealed that 1 and 2 strongly bind to herring-sperm DNA (HS-DNA), though by different binding modes.

Antibacterial effects of a monoporphyrinato ytterbium(III) complex and its free components on Staphylococcus aureus as determined by stop-flow microcalorimetry.

The antibacterial effect of Yb3+, the free porphyrin base 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin (H2TMP; 1), and the corresponding Yb3+ porphyrinato complex [Yb(III)(TMP)(H2O)3]+ Cl- (Yb(TMP); 2) towards Staphylococcus aureus was investigated by stop-flow microcalorimetry. By analyzing the obtained metabolic thermogenic curves, crucial parameters such as rate constant of bacterial growth (k), half inhibitory concentration (IC50), and generation time (t(G)) were determined. The antibacterial activities of the three compounds tested was 2>1>Yb3+, with an IC50 value of 273 mg/l for complex 2. The Yb3+ porphyrinato complex is proposed to benefit from synergetic effects of Yb3+ and the free porphyrin 1.

Novel ebselen-porphyrin conjugates: synthesis and nucleic acid interaction study.

Novel porphyrins bearing ebselen (2-phenyl-1,2-benzisoselenazol-3[2H]-one) moiety were synthesized and characterized. Their interactions with herring sperm DNA were studied by means of UV-visible, fluorescence, circular dichroism spectroscopy, and gel electrophoresis.

[Thermochemical studies on the binding reaction of perseleno diphenyl 2,2'-diformic acid with bovine serum albumin].

The binding of newly compounded perseleno diphenyl 2,2'-diformic acid to bovine serum albumin(BSA) was studied at different temperatures using fluorescence spectrum and UV spectrum. The fluorescence quenching data was analyzed according to Stern-Volmer equation and Lineweaver-Burk double-reciprocal equation. It was showed that this quenching complies better with the charactristic of static fluorescence quenching. The binding constant, thermodynamic parameters, and the binding spot of the compound with certain structure, coming from perseleno diphenyl 2,2'-diformic acid and bovine serum albumin, were obtained. Besides, themechanism of static fluorescence quenching and the quality of binding power were both discussed. The information of the binding mode, the mechanism of its transportation, and some medical theories in human body were offered.

Behavior of new complexes of tetrakis(4-methoxylphenyl)porphyrin with heavy rare earth elements in reversed-phase high performance liquid chromatography.

An HPLC method has been developed for the separation of new complexes of tetrakis(4-methoxylphenyl)porphyrin (TMOPP) with four heavy rare earth elements (RE = Y, Er, Tm, and Yb). The function of amine and acid in the mobile phase has been investigated and a reasonable explanation is presented. Successful separation of the RE-TMOPP-Cl complexes is accomplished in 10 min with a mobile phase consisting of methanol-water-acetic acid-triethanolamine. The detection limits (S/N= 3) for the four complexes are 0.01 microg/mL. This method is rapid, sensitive, and simple.