Porphyrin

The use of a 5,10,15,20-tetrakis(3,4,5-trihydroxyphenyl)porphyrin has yielded a new MOF based on M-1,2,3-trioxobenzene chains that can be made of M = Zr(iv) or RE(iii) (RE = rare earth), showing a very high and limited chemical stability, respectively. The robust metallated Zr-analogue, Co-MIL-173(Zr), has proven to be a heme-like heterogeneous catalyst suitable for aerobic oxidation of hydrocarbons.

BACKGROUND: Hepatitis C virus (HCV) infection is a common susceptibility factor for porphyria cutanea tarda (PCT). Experience on HCV treatment in patients with PCT is limited. Recently, HCV treatment has improved with direct-acting antivirals (DAA). We review our experience on HCV treatment in patients with PCT with older and newer regimens. MATERIALS AND METHODS: A retrospective chart review was conducted. HCV treatment was attempted 22 times in 13 patients with PCT (5 attempts in 1, 2 in 5 and 1 in the other 7 patients)...

Self-assembly of perylene derivative such as N,N'-bis(2(trimethylammonium iodide) ethylene)perylene-3,4,9,10-tetracarboxyldiimide (TAIPDI) can produce one-dimensional form (1D) in an aqueous media. The ability of one-dimensional TAIPDI to form light harvesting complex with water-soluble zinc porphyrin (ZnTPPS4) via the π-π and electrostatic interactions has been described. Owing to electronic interactions between the π-systems, the complex formation is accompanied by pronounced absorption spectral changes in the UV/Vis absorption bands...

Interfacial charge transfer dynamics in dye-sensitized NiO nanoparticles are being investigated for photocathodes in p-type dye-sensitized solar cells. In the photoreaction, after fast electron transfer from NiO to a molecule, the recombination of the hole in the nanoparticles with the electron in a reduced molecule plays an important role in the charge separation process and solar energy harvesting. Nevertheless, knowledge of the interfacial charge recombination (CR) rate and its mechanism is still limited due to the complex photoinduced electron and hole dynamics and lack of characterization of the inhomogeneity of the dynamics...

Gastric cancer (GC) is the 3(rd) deadliest cancer worldwide, due to limited treatment options and late diagnosis. Human epidermal growth factor receptor-2 (HER2) is overexpressed in ∼20% of GC cases and anti-HER2 antibody trastuzumab in combination with conventional chemotherapy, is recognized as standard therapy for HER2-positive metastatic GC. This strategy improves GC patients' survival by 2-3 months, however its optimal results in breast cancer indicate that GC survival may be improved. A new photoimmunoconjugate was developed by conjugating a porphyrin with trastuzumab (Trast:Porph) for targeted photodynamic therapy in HER2-positive GC...

Acute intermittent porphyria (AIP) is a rare autosomal dominant hepatic porphyria due to deficiency of hydroxymethylbilane synthase (HMBS), also known as porphobilinogen deaminase leading to accumulation of porphyrin precursors. However, gene defect alone is usually not sufficient to cause an acute attack, and many extrinsic factors play a role. Diagnostic tests are defined, but clinical suspicion is often delayed as symptoms mimic other common conditions. We report a case of a 18-year-old male with severe, persistent, and generalized abdominal pain along with marked hyponatremia, with subsequent development of altered mentation needing intensive care...

Lead poisoning (LP) is less commonly encountered in emergency departments (ED). However, lead exposure still occurs, and new sources of poisoning have emerged. LP often goes unrecognized due to a low index of suspicion and nonspecific symptoms. We present a case of a 48-year-old man who had recurring abdominal pain with anemia that was misdiagnosed. His condition was initially diagnosed as nonspecific abdominal pain and acute porphyria. Acute porphyria-like symptoms with a positive urine porphyrin test result led to the misdiagnosis; testing for heme precursors in urine is the key to the differential diagnosis between LP and acute porphyria...

A zinc trisporphyrinate has been developed as a chirality sensor for chiral mono-alcohols. In its structure, there are two "spaces" surrounded by three porphyrin moieties, which allow guests to fill in. It has shown extremely high CD sensitivity for a chiral mono-alcohol with a naphthyl substituent, 1-(1-naphthyl)ethanol, at μM level, which is at least three orders of magnitude lower concentration than previous reports. A crystallographic study of the host-guest complex reveals the binding of 1-(1-naphthyl)ethanol to the zinc trisporphyrinate is greatly enhanced by multipoint interactions, such as coordination interactions, hydrogen bonding, π-π and CH···π interactions etc...

Triptolide (TP) from Tripterygium wilfordii has been demonstrated to possess anti-inflammatory, immunosuppressive, and anticancer activities. TP is specially used for the treatment of awkward rheumatoid arthritis, but its clinical application is confined by intense side effects. It is reported that licorice can obviously reduce the toxicity of TP, but the detailed mechanisms involved have not been comprehensively investigated. The current study aimed to explore metabolomics characteristics of the toxic reaction induced by TP and the intervention effect of licorice water extraction (LWE) against such toxicity...

Main group complexes are shown to be viable electrocatalysts for the H2-evolution reaction (HER) from acid. A series of antimony porphyrins with varying axial ligands were synthesized for electrocatalysis applications. The proton-reduction catalytic properties of the compound TPSb(OH)2 (TP = 5,10,15,20-tetra(p-tolyl)porphyrin) with two hydroxyl axial ligands was studied in detail, demonstrating catalytic H2 production. Experiments, in conjunction with quantum chemistry calculations, show that the catalytic cycle is driven via the redox activity of both the porphyrin ligand and the Sb center...

EGFR inhibitors, even with therapeutics superiorities in anticancer, can cause idiosyncratic pulmonary and hepatic toxicities that are associated with the reactive electrophile bioactivated by Cytochrome P450s (P450s). Until now, neither has the electrophilic intermediate been caught experimentally, nor has the subtle mechanism been declared. Herein, the underlying mechanism of bioactivation mediated by P450s was explored by DFT calculations for a case of EGFR inhibitor, Erlotinib. Based on the calculation and analysis, we suggest that with other metabolites, reactive electrophiles of Erlotinib: epoxide and quinine-imine, can be generated by several steps along the oxidative reaction pathway...

We have studied collisions between tetraphenylporphyrin cations and He or Ne at center-of-mass energies in the range 50-110 eV. The experimental results were interpreted in view of density functional theory calculations of dissociation energies and classical molecular dynamics simulations of how the molecules respond to the He/Ne impact. We demonstrate that prompt atom knockout strongly contributes to the total destruction cross sections. Such impulse driven processes typically yield highly reactive fragments and are expected to be important for collisions with any molecular system in this collision energy range, but have earlier been very difficult to isolate for biomolecules...

The development of methods for the generation of site-selective interstrand crosslinks (ICLs) in synthetic oligonucleotides provides a platform for the study of ICL repair mechanisms and the stabilisation of DNA-based materials. Our group has previously reported on the use of a furan moiety as a masked reactive functionality for ICL generation and recently introduced the use of (1)O2 as an efficient light-induced oxidant. Here, the use of porphyrin-based photosensitizers (PSs) has been explored for ICL generation...

We report the use of a novel functionalized porphyrin of [5,15-Bis(ethynyl)-10,20-diphenylporphinato]copper(II) (CuDEPP) as electrodes for rechargeable batteries with extraordinary combination of storage capacity, rate capability, and cycling stability. The ability of CuDEPP serving as an electron donor or acceptor supports diverse applications in battery systems. In a lithium (Li) based half-cell, the CuDEPP cathode exhibits a long cycle life of several thousand cycles and fast charge-discharge rate up to 53 C...

A novel type of porous organic frameworks, based on Mg-porphyrin, with diamond-like topology, named POF-Mgs is computationally designed, and the gas uptakes of CO2 , H2 , N2 , and H2 O in POF-Mgs are investigated by Grand canonical Monte Carlo simulations based on first-principles derived force fields (FF). The FF, which describes the interactions between POF-Mgs and gases, are fitted by dispersion corrected double-hybrid density functional theory, B2PLYP-D3. The good agreement between the obtained FF and the first-principle energies data confirms the reliability of the FF...

Here, the potential of colorimetric sensors utilizing porphyrin indicators for long term environmental monitoring is demonstrated. Prototype devices based on commercial color sensing chips (six per device) were combined with in-house developed algorithms for data analysis. The devices are intended to provide real-time sensing of threats. An initial outdoor data set was collected using prototype devices with occasional spiked exposure to targets. This data was supported by similar data collected in a controlled indoor environment...

Cytochrome P450 55B1 from Chlamydomonas reinhardtii is reported to function as a nitric oxide reductase (NOR). Here, we expressed the cytochrome P450 55B1 gene with an HIS-tag in E scherichia coli using a pET28a vector. The native protein was produced at a level of 1.59 μmol/g of total protein, with approximately 85% of the P450 being soluble. The CYP55B1 protein was characterized spectrally and purified by a HIS-trap column. This procedure allowed recovery of 45% of the expressed protein and CYP55B1 with a specific content of 0...

Neuroblastoma (NB) is a pediatric tumor presenting at diagnosis either as localized or metastatic disease, which mainly involves the bone marrow (BM). The physical occupancy of BM space by metastatic NB cells has been held responsible for impairment of BM function. Here, we investigated whether localized or metastatic NB may alter hematopoietic lineages' maturation and release of mature cells in the periphery, through gene expression profiling, analysis of BM smears, cell blood count and flow cytometry analysis...

We have investigated the accumulation of porphyrins in Propionibacterium acnes (P.acnes) by 5-aminolevulinic acid hydrochloride (ALA) and its esters, ALA methyl ester hydrochloride (mALA), ALA octyl ester hydrochloride (oALA), and ALA benzyl ester hydrochloride (bALA). From the fluorescence spectra of porphyrins accumulated in P.acnes, the order of porphyrin accumulation is as follows: ALA≫mALA≈bALA>oALA (≈0). Moreover, the PDT efficacy is reduced in the order of ALA>mALA≈bALA>oALA (≈without additives)...

Porphyrin tapes possessing meso-meso β-β β-β triple direct linkages have been targets of extensive studies because of their fully conjugated characteristic π-electronic networks. In this paper, we report porphyrin arch-tapes that bear additional carbonyl group(s) or methylene group(s) inserted between one of the β-β linkage(s) of the porphyrin tapes. The carbonyl-inserted porphyrin arch-tapes were efficiently synthesized by double fusion reactions of β-to-β carbonyl-bridged porphyrin oligomers with DDQ and Sc(OTf)3, and were converted to the methylene-bridged porphyrin arch-tapes via Luche reduction with NaBH4 and CeCl3 followed by ionic hydrogenation with HBF4·OEt2 and BH3·NEt3...