Recently, the best catalyst for benzene to phenol oxidation by nitrous oxide is Fe-ZSM-5 zeolite, which provides nearly 100% benzene selectivity, but low conversion of benzene . The remarkable catalytic performance of this zeolite was show to be related to the presence of iron and upon high temperature treatment. In these systems, the reaction only occurs in the gas phase (ca. 300º) and there is no report on single-step liquid phase oxidation of benzene to phenol in the literature. For these reasons, in this research, we will study the single-step liquid phase oxidation of benzene to phenol using iron(III)-porphyrin supported on Al-MCM-41 and polymethacrylic acid (PMAA).
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(Received 29 October 2012; revised manuscript received 17 May 2013; published 1 July 2013) One of the key factors behind the rapid evolution of molecular spintronics is the efficient realization of spin manipulation of organic molecules with a magnetic center. The spin state of such molecules may depend crucially on the interaction with the substrate on which they are adsorbed. In this paper we demonstrate, using ab initio density functional calculations, that the stabilization of a high spin state of an iron porphyrin (FeP) molecule can be achieved via chemisorption on magnetic substrates of different species and orientations, viz., Co(001), Ni(001), Ni(110), and Ni(111). The signature of chemisorption of FeP on magnetic substrates is evident from broad features in N K x-ray absorption (XA) and Fe L 2,3 x-ray magnetic circular dichroism (XMCD)
It has been suggested that the most important driving forces for the formation of the complex are π-π and hydrophobic interactions between the porphyrin ring and quinoline ring. The coordination of the iron center of Ferri-porphyrin by the alcohol/alkoxy functionality and an intramolecular hydrogen bond formed between the protonated quaternary quinuclidine nitrogen atom of a drug molecule and the negatively charged propionate side chain of the Ferri-porphyrin have been also mentioned as additional forces stabilizing the complex    . Growing resistance of the Plasmodium to the quinoline antimalarials spurred the development of a new antimalarial pharmacological approach based on designing new molecules  . A new antimalarial chemotherapy has been reported based on choline analogues with novel mechanisms of action  . The authors reported that these drugs are “dual molecules”, structurally unrelated to existing antimalarial agents, acting through two mechanisms: they interact with the plasmodial phospholipid metabolism and also with the malarial FePPIX polymer. However, quantitative studies of the interaction of the iron (III) porphyrin FePPIX in pure aqueous solution, the physiological medium, are hampered by the tendency of FePPIX to form aggregates considerably larger than dimers. In weakly acid and neutral solutions of FePPIX, a stable state can- not be achieved probably due to colloidal precipitation leading to artefacts in quantitative investigations      . FeTPPS is sufficiently so- luble in aqueous solution in a wide pH range due to four very strong acid groups (SO 3 H) compared to two weak acid groups (-CH 2 CH 2 CO 2 H) of FePPIX. Dimeri-
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Mesoporous MCM-41 with its hexagonally ordered struc- ture has attracted much attention because of their potential use as catalyst supports [10–14]. Transition metal com- plexes and organometallic compounds can be encapsulated in the mesoporous MCM-41 supports by physical adsorp- tion or covalent linkage. More recently, much effort was focused on the encapsulation of metalloporphyrins in the pore of MCM-41 [15–18]. For example, Che and coworkers  have immobilized a ruthenium porphyrin on modified MCM-41. However, the MCM-41, an inorganic material, is hydrophilic and rigid. In this study, we also propose a proce- dure to encapsulate iron-porphyrin on the polymer support, namely poly(methacrylic acid) (PMAA). One expects that
examined the protonation reactions of reduced clusters and the generation of dihydrogen by using several heterometals (eg. Fe, Mo, W, Ni) [13-18]. Bhugun et al.  reported on the catalysis of electrochemical reduction of proton by using an iron meso-tetraphenylporphyrin (TPP) in the presence triethylamine as source of proton. In this context, much effort has been focused on the development of novel model of porphyrin mimics such as cobalt-, iron-, osmium- or ruthenium- porphyrins [20,21].
Metal-porphyrins were also employed to catalyze in situ photopolymerization of soil humic matter. In fact, both a water-soluble iron-porphyrin and a manga- nese-porphyrin immobilized on spacer-functionalized montmorillonite were found to couple humic phenolic molecules in the soil complex matrix by photo-oxidation under solar radiation [23–26]. However, up to our knowl- edge, no investigation has been reported so far on the in situ oxidative polymerization of soil humic molecules under biomimetic catalysis in the presence of a chemi- cal oxidant. Therefore, the objective of this work was to investigate the enhancement in chemical stability of SOM when a soil was subjected to oxidative catalysis, by applying in situ a water-soluble iron-porphyrin and H 2 O 2
Senge, M. O. (2000a). The Porphyrin Handbook, Vol. 10, edited by K. M. Kadish, R. Guilard & K. M. Smith, pp. 1±218. San Diego: Academic Press. Senge, M. O. (2000b). The Porphyrin Handbook, Vol. 1, edited by K. M. Kadish, R. Guilard & K. M. Smith, pp. 239±347. San Diego: Academic Press. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of
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www.wjpr.net Vol 3, Issue 10, 2014. 1614 thrombosis in the vascular system. Free radical generation in the living systems is also one such important aspect of life processes. Free radicals are highly reactive species of molecules generated in the cell by the oxidative mechanisms. These oxidative mechanism events are set forth by certain chemical moieties which have deleterious effect on the cellular genetic material such as DNA. Any damage at the DNA level is deleterious and are potent carcinogenic or mutagenic in nature. The chemical molecules that accommodate the transition metals such as platinum, iron, copper, zinc, chromium and tin can strongly bind to nucleic acids and chemical skeletons such as quinolones have displayed mechanisms of oxidative stress and free radical generation. Identification of such molecules that have implications in the oxidative stress at an early stage helps in better understanding of the Structure Based Drug Design (SBDD). There are several methods for assessing the carcinogenic or mutagenic properties of the given chemical structure. The method followed here is a bacterial strain based assay which includes E.coli AB1157 which is a wild-type strain proficient in DNA damage repair. This bacterial strain is incubated with the compounds/chemical structures of interest i.e. axially ligated indium (III) porphyrins for the analysis of any associated lethal effects. On incubation with the compounds, any free radical generation by the compounds leads to lethality of the cells. This cytotoxic potentiality of the compound will be displayed in terms of zone of inhibition. This study therefore provides an early indication of the compound’s capability of free radical generation and cautions the researcher for further understanding of compound’s carcinogenic or mutagenic potential in various models or studies.
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Many iron porphyrin complexes have been synthesized as models for the study of the important roles that heme enzymes play in biological processes. In this paper, we report the first structure of the title compound, (I), five-coordinate (tri- fluoromethanesulfonato)(octaethylporphinato)iron(III). Other trifluoromethanesulfonato iron porphyrin derivatives have been reported previously: The (T piv PP)Fe(OSO 2 CF 3 )(H 2 O) compound is six-coordinate at Fe, and the (TPP)Fe(OSO 2 CF 3 )
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particular were bactericidal (in the dark) compared to most other metals. 20 It so happens that both Ga-PPIX and In-PPIX are highly effective photosensitizer due to the heavy atom effect, which increases the lifetime of the triplet state. In a set of experiments involving E. coli and Y. enterocolitica mutants of heme uptake pathway as well as by altering the level of available iron and heme in the medium, Stojiljkovic et al. demonstrated that these metalloporphyrins were recognized by heme receptors on the cell surface. It should be noted that the uptake of these porphyrins into the cells was not examined by Stojiljkovic et al. Only the growth inhibition was explained by inhibition of some vital function by these metal ions. Therefore it is uncertain whether other metalated porphyrins (e.g., Zn(II) or Pd(II)] that were not found to be highly effective, were or were not recognized by heme receptors, because these metalloporphyrins may not have had any toxicity. A study looked at some variations in the structure of heme and porphyrin analogues and their recognition by heme receptors in P. gingivalis. 21 In so doing, the central metal and vinyl groups were found to have small effects
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Secondary end points also significantly favored feru- moxytol treatment. Fifty-one percent of ferumoxytol-treated patients achieved a Hgb level $120 g/L at any time from baseline to Week 5 compared to none of the patients who received placebo (treatment difference: 51.4%; P,0.001). In addition, the mean change in TSAT values from baseline to Week 5 was significantly greater for ferumoxytol-treated patients compared with placebo-treated patients (treatment difference: 11.2%; P,0.001), demonstrating the successful repletion of iron stores with ferumoxytol. Mean TSAT values in ferumoxytol-treated patients increased rapidly from baseline through Week 2 and then declined slightly through Week 5 as the Hgb levels increased (Figure 3), likely due to iron utilization for hematopoiesis. There was little-to-no change in TSAT in the placebo treatment group.
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In the study of Resonance Raman spectra of Octaethyl dimers, we have applied one dimensional algebraic model i.e. U(2) Vibron model. In this study we reported RMS deviation and the locality parameter () for Oxy- gen and Nitrogen-Bridged Iron Octaethylporphyrin dimmers of in-plane skeletal modes at λ = 4067 Å and also for OEPFecl at λ = 5208 Å, (OEPFe) 2 O at λ = 5682
In oxygenic phototrophs, chlorophylls, hemes and bilins are synthesized by a common branched pathway. Given the phototoxic nature of tetrapyrroles, this pathway must be tightly regulated and an important regulatory role is attributed to Mg- chelatase enzyme at the branching between the heme and chlorophyll pathway. Gun4 is a porphyrin-binding protein known to stimulate in vitro the Mg-chelatase activity but how the Gun4-porphyrin complex acts in the cell was unknown. To address this issue we first performed simulations to determine the porphyrin-docking mechanism to the cyanobacterial Gun4 structure. After correcting crystallographic loop contacts, we determined the binding site for Mg- protoporphyrin IX. Molecular modeling revealed that the orientation of α6/α7 loop is critical for the binding and the magnesium ion held within the porphyrin is coordinated by Asn211 residue. We also identified the basis for stronger binding in the Gun4-1 variant and for weaker binding in the W192A mutant. The W192A-Gun4 was further characterized in Mg-chelatase assay showing that tight porphyrin-binding in Gun4 facilitates its interaction with the Mg-chelatase ChlH subunit. Finally, we introduced the W192A mutation into cells and show that the Gun4- porphyrin complex is important for the accumulation of ChlH and for channeling
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The safety population included all randomized patients who had any exposure to the study drug and was based on actual treatment received. The intent-to-treat (ITT) population included any randomized patient who had any exposure to the study drug (IV ferumoxytol, IV iron sucrose, IV saline placebo) and was based upon randomized treatment assign- ment. The safety and ITT populations were identical in this analysis. Demographics and baseline characteristics were compared between treatment groups using the Fisher exact test for categorical variables (sex, race, type of cancer, history of IV iron use, and Hgb category) and analysis of variance for continuous variables (Hgb, TSAT, and serum ferritin). In the overall study population, changes from baseline in con- tinuous variables were compared between treatment groups using analysis of covariance controlling for baseline Hgb value, using an imputed value of 0 for change from baseline for missing post-baseline values. In this cancer subgroup analysis, within-group differences in change from baseline Hgb and FACIT-F were analyzed with a paired t-test. The incidence of blood transfusions and use of ESAs were sum- marized using descriptive statistics.
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We present the validation of a developed a new spectrophotometric method based on a charge transfer complexation reaction of heterocyclic ring containing drug. In this method, the oxidation of chlorapromazine drug. In this method, the oxidation of Promethazine drug by a known excess amount of cerium IV sulphate in acid medium, the unreacted cerium IV sulphate is treated with Iron II Sulphate, After 5 minutes the resultant Iron III Sulphate solution was treated with (1M) Ammonium thiocyanate, immediately it forms blood red colour of Iron III Sulphate – thiocyanate drug complex. This blood red coloured complex formed under standardized conditions was measured at 480 mm, Beer’s law was obeyed for 10- 40 µg / ml -2 of Promethazine. Results of analysis were validated statistically and by recovery studies. The procedures described were successfully applied to the determination of Promethazine bulk drug form and in tablets. Key Words: Promethazine spectrometric cerium IV sulphate, Iron III Sulphate (ammonium ferrous sulphate solution) Ammonium thiocyanate solution.
was structurally determined, omitting the H atoms, by Kita- hama et al. (1975), and the H-atom positions were discussed by Hawthorne (1976). However, the O—H bond lengths and angles were not completely satisfactory. In this work, we synthesized and redetermined the title compound, iron(III) arsenate dihydrate, and the H atoms were clearly located with satisfactory bond lengths and angles. Additionally, the s.u values of the bond lengths could be improved by a factor of two compared with the previous structure determination.
Structure and stability of Porphyrin, complexity of Metal ions with Porphyrin and Metal ions bonded dimer of them Structure of species involve in formation of dimers of porphyrin include; Metal ions bonded to porphyrin and Metal ions bonded dimer of them was calculated by methods as mentioned previously. The optimized structure of the Metal ions bonded to porphyrin and magnesium ion bonded dimer of them respectively are shown in Fig.3. Fig.4. and Fig.5.
Apart from the UTMD technique, the PGL-MBs were also the primary means of PS accumulation. To the best of our knowledge, PGL-MBs are the first reported porphyrin-loaded MBs used for PDT. As previously mentioned, the ingenious structure of PGL endows PGL-MBs with the superiorities of high PS loading content and resistance to PSs self-quenching caused by π-π interactions. These features could overcome the shortcomings of conventional PS- loaded MBs. In addition, owing to the amphipathicity of PGL, PGL-MBs after US destruction transformed into small nanoparticles, which then passed through the gaps between epithelial cells of tumor vessels and entered the tumor cells. All of these factors ensured sufficient accumulation of PGL and subsequent exertion of phototoxic effects at the tumor site.
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Also, iron can act as a source material for an unpleasant taste or odor in water. In addition, precipitates of iron form turbidity, which limits the usage of water for drinking or industrial processes. Since iron in the wastewater is able to induce several problems, it has been regarded as one of the major target materials to be removed [Bereket G. et al. (1997)]. In order to control iron content in water, many types of treatment technologies have been utilized, such as precipitation, electrochemical deposition, solvent extraction, ion exchange and adsorption, etc. [Uchida M. et al. (1999) - Pakula M. et al. (1998) - Huang C. and Cheng W.P. (1997) - Kato M. et al. (1998) - Belous A.G. et al. (2000) - Fahlman M. et al. (1998) - Voropanova L.A. and Velichko L.N. (1999) - Zarraa M.A. (1999)].
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third of the population of the world. Anemia is the most common clinical manifestation of iron deficiency, but, other organs and systems may also be affected. Cognitive dysfunction, psychomotor retardation, behavioral impairments, pica, breath holding spells, restless leg syndrome and thrombosis could be associated with iron deficiency. Effect of iron deficiency in the developing brain and mechanisms such as altered development of hippocampus neurons, impairment of energy metabolism, delayed maturation of myelin, slowed visual and auditory evoked potentials and alterations in synaptic neurotransmitter systems including