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1.
Inorg Chem ; 63(30): 13893-13902, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39011904

ABSTRACT

Two new p-cresol-2,6-bis(amide-tether-dpa4-X) ligands (HL4-X, X = MeO and Cl) and their dicopper complexes [Cu2(µ-1,1-OAc)(µ-1,3-OAc)(L4-MeO)]Y (Y = PF6 1a, OAc 1b) and [Cu2(µ-1,3-OAc)2(L4-Cl)]Y (Y = ClO4 2a, OAc 2b) were synthesized. The electronic and hydrophobic effects of the MeO and Cl groups were examined compared with nonsubstituted complex [Cu2(µ-1,1-OAc)(µ-1,3-OAc)(L)]+ (3). The electronic effects were found in crystal structures, spectroscopic characterization, and redox potentials of these complexes. 1b and 2b were reduced to Cu(I)Cu(I) with sodium ascorbate and reductively activated O2 to produce H2O2 and HO•. The H2O2 release and HO• generation are promoted by the electronic effects. The hydrophobic effects increased the lipophilicity of 1b and 2b. Cellular ROS generation of 1b, 2b, and 3 was visualized by DCFH-DA. To examine the intracellular behavior, boron dipyrromethene (Bodipy)-modified complexes 4B and 5B corresponding to 1b and 2b were synthesized. These support that 1b and 2b are localized at the ER and Golgi apparatus. The cytotoxicity of 1b and 2b against various cell lines was examined by MTT assay. 1b and 2b were 7- and 41-fold more cytotoxic than 3. 1b generated ROS selectively in cancer cell but 2b nonselectively in cancer and normal cells, causing cancer- and normal-cell-selective cytotoxicity, respectively.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Copper , Hydrophobic and Hydrophilic Interactions , Reactive Oxygen Species , Humans , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Reactive Oxygen Species/metabolism , Copper/chemistry , Copper/pharmacology , Drug Screening Assays, Antitumor , Molecular Structure , Cresols/chemistry , Cresols/pharmacology , Cresols/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Cell Proliferation/drug effects , Electrons , Amides/chemistry , Amides/pharmacology , Amides/chemical synthesis
2.
Inorg Chem ; 60(8): 5474-5482, 2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33259197

ABSTRACT

Dicopper complexes of a new p-cresol-2,6-bis(dpa) amide-tether ligand (HL1), [Cu2(µ-OH2)(µ-1,3-OAc)(L1)](ClO4)2 (1) and [Cu2(µ-1,1-OAc)(µ-1,3-OAc)(L1)]X (X = ClO4 (2a), OAc (2b)) were synthesized and structurally characterized. 2b rapidly cleaves supercoiled plasmid DNA by activating H2O2 at neutral pH to a linear DNA and shows remarkable cytotoxicity in comparison with related complexes. As 2b is more cytotoxic than HL1, the dicopper core is kept in the cell. A boron dipyrromethene (Bodipy)-modified complex of the p-cresol-2,6-bis(dpa) amide-tether ligand having a Bodipy pendant (HL2), [Cu2(µ-OAc)2(L2)](OAc) (3), was synthesized to visualize intracellular behavior, suggesting that 2b attacks the nucleolus and mitochondria. A comet assay clearly shows that 2b does not cleave nuclear DNA. The apoptotic cell death is evidenced from flow cytometry.


Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Copper/pharmacology , Cresols/pharmacology , DNA/drug effects , Amides/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line , Cell Proliferation/drug effects , Cell Survival/drug effects , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Copper/chemistry , Cresols/chemistry , DNA Cleavage , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Hydrogen Peroxide/antagonists & inhibitors , Hydrogen Peroxide/pharmacology , Ligands , Molecular Structure , Optical Imaging , Oxidation-Reduction , Plasmids
3.
Mol Biol Rep ; 48(5): 4549-4561, 2021 May.
Article in English | MEDLINE | ID: mdl-34129187

ABSTRACT

Insect odorant receptors (ORs) have been suggested to function as ligand-gated cation channels, with OrX/Orco heteromers combining ionotropic and metabotropic activity. The latter is mediated by different G proteins and results in Orco self-activation by cyclic nucleotide binding. In this contribution, we co-express the odor-specific subunits DmOr49b and DmOr59b with either wild-type Orco or an Orco-PKC mutant lacking cAMP activation heterologously in mammalian cells. We show that the characteristics of heteromers strongly depend on both the OrX type and the coreceptor variant. Thus, methyl acetate-sensitive Or59b/Orco demonstrated 25-fold faster response kinetics over o-cresol-specific Or49b/Orco, while the latter required a 10-100 times lower ligand concentration to evoke a similar electrical response. Compared to wild-type Orco, Orco-PKC decreased odorant sensitivity in both heteromers, and blocked an outward current rectification intrinsic to the Or49b/Orco pair. Our observations thus provide an insight into insect OrX/Orco functioning, highlighting their natural and artificial tuning features and laying the groundwork for their application in chemogenetics, drug screening, and repellent design.


Subject(s)
Drosophila Proteins/genetics , Ligand-Gated Ion Channels/genetics , Receptors, Odorant/genetics , Acetates/chemistry , Acetates/pharmacology , Animals , Cresols/chemistry , Cresols/pharmacology , Cyclic AMP/genetics , Drosophila melanogaster/genetics , Drosophila melanogaster/physiology , GTP-Binding Proteins/genetics , Kinetics , Odorants/analysis , Signal Transduction/drug effects
4.
Chembiochem ; 21(18): 2643-2658, 2020 09 14.
Article in English | MEDLINE | ID: mdl-32307798

ABSTRACT

The conjugation of organometallic complexes to known bioactive organic frameworks is a proven strategy revered for devising new drug molecules with novel modes of action. This approach holds great promise for the generation of potent drug leads in the quest for therapeutic chemotypes with the potential to overcome the development of clinical resistance. Herein, we present the in vitro antiplasmodial and antiproliferative investigation of ferrocenyl α-aminocresol conjugates assembled by amalgamation of the organometallic ferrocene unit and an α-aminocresol scaffold possessing antimalarial activity. The compounds pursued in the study exhibited higher toxicity towards the chemosensitive (3D7) and -resistant (Dd2) strains of the Plasmodium falciparum parasite than to the human HCC70 triple-negative breast cancer cell line. Indication of cross-resistance was absent for the compounds evaluated against the multi-resistant Dd2 strain. Structure-activity analysis revealed that the phenolic hydroxy group and rotatable σ bond between the α-carbon and NH group of the α-amino-o-cresol skeleton are crucial for the biological activity of the compounds. Spectrophotometric techniques and in silico docking simulations performed on selected derivatives suggest that the compounds show a dual mode of action involving hemozoin inhibition and DNA interaction via minor-groove binding. Lastly, compound 9 a, identified as a possible lead, exhibited preferential binding for the plasmodial DNA isolated from 3D7 P. falciparum trophozoites over the mammalian calf thymus DNA, thereby substantiating the enhanced antiplasmodial activity of the compounds. The presented research demonstrates the strategy of incorporating organometallic complexes into known biologically active organic scaffolds as a viable avenue to fashion novel multimodal compounds with potential to counter the development drug resistance.


Subject(s)
Antimalarials/pharmacology , Antineoplastic Agents/pharmacology , DNA, Fungal/drug effects , Hemeproteins/antagonists & inhibitors , Organometallic Compounds/pharmacology , Plasmodium falciparum/drug effects , Antimalarials/chemical synthesis , Antimalarials/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cresols/chemistry , Cresols/pharmacology , Drug Screening Assays, Antitumor , Ferrous Compounds/chemistry , Ferrous Compounds/pharmacology , Hemeproteins/metabolism , Humans , Metallocenes/chemistry , Metallocenes/pharmacology , Microbial Sensitivity Tests , Molecular Docking Simulation , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry
5.
Phys Rev Lett ; 125(24): 243902, 2020 Dec 11.
Article in English | MEDLINE | ID: mdl-33412069

ABSTRACT

Dispersive shock waves in thermal optical media are nonlinear phenomena whose intrinsic irreversibility is described by time asymmetric quantum mechanics. Recent studies demonstrated that the nonlocal wave breaking evolves in an exponentially decaying dynamics ruled by the reversed harmonic oscillator, namely, the simplest irreversible quantum system in the rigged Hilbert spaces. The generalization of this theory to more complex scenarios is still an open question. In this work, we use a thermal third-order medium with an unprecedented giant Kerr coefficient, the m-cresol/nylon mixed solution, to access an extremely nonlinear, highly nonlocal regime and realize anisotropic shock waves with internal gaps. We compare our experimental observations to results obtained under similar conditions but in hemoglobin solutions from human red blood cells, and found that the gap formation strongly depends on the nonlinearity strength. We prove that a superposition of Gamow vectors in an ad hoc rigged Hilbert space, that is, a tensorial product between the reversed and the standard harmonic oscillators spaces, describes the beam propagation beyond the shock point. The anisotropy turns out from the interaction of trapping and antitrapping potentials. Our work furnishes the description of novel intriguing shock phenomena mediated by extreme nonlinearities.


Subject(s)
Models, Theoretical , Optics and Photonics/methods , Anisotropy , Computer Simulation , Cresols/chemistry , Erythrocytes/chemistry , Hemoglobins/chemistry , Humans , Nonlinear Dynamics , Nylons/chemistry , Quantum Theory
6.
Mikrochim Acta ; 187(7): 388, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32542460

ABSTRACT

A novel magnetic organic porous polymer (denoted as Fe3O4@PC-POP) was developed for magnetic solid-phase extraction (MSPE) of two gastric cancer biomarkers (P-cresol and 4-hydroxybenzoic acid) from urine samples prior to high-performance liquid chromatographic analysis. The adsorbent was characterized by scanning electron microscope, transmission electron microscope, FTIR, powder X-ray diffraction, and other techniques. The result of dynamic light scattering shows that the particle size of the adsorbent is mainly distributed around 400 nm. Based on the design concept of the Fe3O4@PC-POP, the proposed material can effectively capture the target analytes through electrostatic and hydrophobic interaction mechanism. Furthermore, the enrichment conditions were optimized by the response surface method, and the method was utilized for the determination of P-cresol and 4-hydroxybenzoic acid in real urine samples from health and gastric cancer patients with high enrichment factors (34.8 times for P-cresol and 38.7 times for 4-hydroxybenzoic acid), low limit of detection (0.9-5.0 µg L-1), wide linear ranges (3.0-1000 µg L-1), satisfactory relative standard deviation (2.5%-8.5%), and apparent recoveries (85.3-112% for healthy people's and 86.0-112% for gastric cancer patients' urine samples). This study provides a guided principle for design of the versatile polymer with specific capturing of the target compounds from complex biological samples. Graphical abstract.


Subject(s)
Biomarkers, Tumor/urine , Cresols/urine , Magnetite Nanoparticles/chemistry , Parabens/analysis , Polymers/chemistry , Stomach Neoplasms/urine , Adsorption , Biomarkers, Tumor/chemistry , Biomarkers, Tumor/isolation & purification , Chromatography, High Pressure Liquid , Cresols/chemistry , Cresols/isolation & purification , Humans , Limit of Detection , Parabens/chemistry , Parabens/isolation & purification , Piperazines/chemistry , Porosity , Solid Phase Extraction/methods
7.
Molecules ; 25(17)2020 Sep 03.
Article in English | MEDLINE | ID: mdl-32899408

ABSTRACT

The two-exponential Sheffield equation of viscosity η(T) = A1·T·[1 + A2·exp(Hm/RT)]·[1 + C·exp(Hd/RT)], where A1, A2, Hm, C, and Hm are material-specific constants, is used to analyze the viscous flows of two glass-forming organic materials-salol and α-phenyl-o-cresol. It is demonstrated that the viscosity equation can be simplified to a four-parameter version: η(T) = A·T·exp(Hm/RT)]·[1 + C·exp(Hd/RT)]. The Sheffield model gives a correct description of viscosity, with two exact Arrhenius-type asymptotes below and above the glass transition temperature, whereas near the Tg it gives practically the same results as well-known and widely used viscosity equations. It is revealed that the constants of the Sheffield equation are not universal for all temperature ranges and may need to be updated for very high temperatures, where changes occur in melt properties leading to modifications of A and Hm for both salol and α-phenyl-o-cresol.


Subject(s)
Glass/chemistry , Organic Chemicals/chemistry , Rheology , Cresols/chemistry , Salicylates/chemistry , Temperature , Viscosity
8.
J Environ Sci Health B ; 55(3): 184-192, 2020.
Article in English | MEDLINE | ID: mdl-31625818

ABSTRACT

Cresols are chemical contaminants derivative from phenol which can be found in sewage sludge. However, little attention has been given to monitoring these compounds in environmental matrices in the literature. Thus, the objective of this study was to develop a simple method based on solid-liquid extraction with low temperature purification for determining three cresol isomers in sludge. The quantification of these compounds was performed by gas chromatography coupled to mass spectrometry with a previous derivatization step. After a detailed study, the cresol recovery was higher than 91%, with relative standard deviation lower than 12% and a limit of quantification of 20 µg kg-1. Linearity was achieved between 10 and 90 µg L-1 (R2 > 0.98) with the standard solutions prepared in matrix extracts due to the trouble caused by the matrix effect. The proposed method was applied with success for monitoring cresols in sewage sludge samples coming from six different wastewater treatment plants. All samples showed contamination by cresols, mainly p-cresol with values between 32.3 and 516.9 µg kg-1. The majority of the analyzed samples showed a total sum of the isomers higher than the maximum residue limit established by Brazilian legislation (160 µg kg-1).


Subject(s)
Chemical Fractionation/methods , Cresols/analysis , Cresols/chemistry , Gas Chromatography-Mass Spectrometry/methods , Sewage/analysis , Brazil , Cresols/isolation & purification , Isomerism , Limit of Detection , Reproducibility of Results , Temperature , Waste Disposal, Fluid
9.
Bull Exp Biol Med ; 169(3): 310-313, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32748134

ABSTRACT

2,6-Diisobornyl-4-methylphenol (Dibornol, 10 mg/kg intragastrically daily for 5 days after myocardial ischemia/reperfusion) 1.5-fold increased rat survival during the acute post-infarction period in comparison with the control group. In survivors, Dibornol reliably prevented post-ischemic progression of heart failure in the delayed post-infarction period (30 days after ischemia/reperfusion), which was seen from an increase in the left-ventricular developed pressure by 22%, left-ventricular contractility index by 19%, and +dP/dt by 34%. Left-ventricular end-diastolic pressure was by 39% lower than in control animals. Morphological study of heart sections from control group animals showed that Dibornol reduced the area of post-ischemic myocardial damage in the delayed period after ischemia/reperfusion to 3±1% (vs 18±2% in the control group).


Subject(s)
Cresols/therapeutic use , Heart Ventricles/drug effects , Myocardial Reperfusion Injury/drug therapy , Animals , Blood Pressure/drug effects , Cresols/chemistry , Heart/drug effects , Heart Ventricles/metabolism , Male , Myocardial Reperfusion , Myocardial Reperfusion Injury/metabolism , Rats
10.
J Am Chem Soc ; 141(6): 2568-2576, 2019 02 13.
Article in English | MEDLINE | ID: mdl-30707010

ABSTRACT

Uremic toxins often accumulate in patients with compromised kidney function, like those with chronic kidney disease (CKD), leading to major clinical complications including serious illness and death. Sufficient removal of these toxins from the blood increases the efficacy of hemodialysis, as well as the survival rate, in CKD patients. Understanding the interactions between an adsorbent and the uremic toxins is critical for designing effective materials to remove these toxic compounds. Herein, we study the adsorption behavior of the uremic toxins, p-cresyl sulfate, indoxyl sulfate, and hippuric acid, in a series of zirconium-based metal-organic frameworks (MOFs). The pyrene-based MOF, NU-1000, offers the highest toxin removal efficiency of all the MOFs in this study. Other Zr-based MOFs possessing comparable surface areas and pore sizes to NU-1000 while lacking an extended aromatic system have much lower toxin removal efficiency. From single-crystal X-ray diffraction analyses assisted by density functional theory calculations, we determined that the high adsorption capacity of NU-1000 can be attributed to the highly hydrophobic adsorption sites sandwiched by two pyrene linkers and the hydroxyls and water molecules on the Zr6 nodes, which are capable of hydrogen bonding with polar functional groups of guest molecules. Further, NU-1000 almost completely removes p-cresyl sulfate from human serum albumin, a protein that these uremic toxins bind to in the body. These results offer design principles for potential MOFs candidates for uremic toxin removal.


Subject(s)
Metal-Organic Frameworks/chemistry , Serum Albumin, Human/metabolism , Uremia/metabolism , Zirconium/chemistry , Adsorption , Cresols/chemistry , Cresols/isolation & purification , Cresols/metabolism , Humans , Kinetics , Models, Molecular , Protein Conformation , Pyrenes/chemistry , Sulfuric Acid Esters/chemistry , Sulfuric Acid Esters/isolation & purification , Sulfuric Acid Esters/metabolism
11.
Analyst ; 144(23): 6975-6980, 2019 Nov 18.
Article in English | MEDLINE | ID: mdl-31631198

ABSTRACT

A novel pH-sensitive fluorescent probe has been designed and synthesized for sensing intracellular pH. This probe showed excellent water solubility, it was sensitive toward the pH range from 4 to 12, and it was especially sensitive in alkaline environments. During the pH changes from acidic to alkaline environments, the color of the solution turned from yellow to purple, thus the difference in color can be used to distinguish between acidic and alkaline systems. The other major features of probe pH-DCN including high selectivity, low toxicity, good reversibility and stability allowed pH-DCN to visualize fluctuations of the pH in live cells. Moreover, probe pH-DCN has successfully discriminated cancer cells from normal cells by monitoring their different intracellular pH levels.


Subject(s)
Cresols/chemistry , Fluorescent Dyes/chemistry , Neoplasms/diagnostic imaging , Animals , Cell Line, Tumor , Colorimetry/methods , Cresols/chemical synthesis , Cresols/toxicity , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/toxicity , HEK293 Cells , Human Umbilical Vein Endothelial Cells , Humans , Hydrogen-Ion Concentration , Mice , Microscopy, Confocal/methods , Microscopy, Fluorescence/methods , RAW 264.7 Cells , Solubility , Water/chemistry
12.
Inorg Chem ; 58(21): 14294-14298, 2019 Nov 04.
Article in English | MEDLINE | ID: mdl-31599154

ABSTRACT

Metal complexes to promote oxidative DNA cleavage by H2O2 are desirable as anticancer drugs. A dicopper(II) complex of known p-cresol-derived methylene-tether ligand Hbcc [Cu2(bcc)]3+ did not promote DNA cleavage by H2O2. Here, we synthesized a new p-cresol-derived amide-tether one, 2,6-bis(1,4,7,10-tetrazacyclododecyl-1-carboxyamide)-p-cresol (Hbcamide). A dicopper(II) complex of the new ligand [Cu2(µ-OH)(bcamide)]2+ was structurally characterized. This complex promoted the oxidative cleavage of supercoiled plasmid pUC19 DNA (Form I) with H2O2 at pH 6.0-8.2 to give Forms II and III. The reaction was largely accelerated in a high pH region. A µ-1,1-hydroperoxo species was formed as the active species and spectroscopically identified. The amide-tether complex is more effective in cytotoxicity against HeLa cells than the methylene-tether one.


Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Copper/pharmacology , Cresols/pharmacology , Hydrogen Peroxide/pharmacology , Amides/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Copper/chemistry , Cresols/chemistry , DNA Cleavage , Drug Screening Assays, Antitumor , HeLa Cells , Humans , Hydrogen Peroxide/chemical synthesis , Hydrogen Peroxide/chemistry , Ligands , Molecular Structure , Oxidation-Reduction
13.
Anesth Analg ; 128(5): 891-900, 2019 05.
Article in English | MEDLINE | ID: mdl-29505449

ABSTRACT

Medications used in anesthesiology contain both pharmacologically active compounds and additional additives that are usually regarded as being pharmacologically inactive. These additives, called excipients, serve diverse functions. Despite being labeled inert, excipients are not necessarily benign substances. Anesthesiologists should have a clear understanding of their chemical properties and the potential for adverse reactions. This report catalogs the excipients found in drugs commonly used in anesthesiology, provides a brief description of their function, and documents examples from the literature regarding their adverse effects.


Subject(s)
Anesthesia/methods , Excipients/adverse effects , Anesthesia/standards , Anesthetics/chemistry , Animals , Benzyl Alcohol/chemistry , Chemistry, Pharmaceutical , Cresols/chemistry , Drug Hypersensitivity , Edetic Acid/chemistry , Excipients/chemistry , Humans , Indocyanine Green/chemistry , Injections, Spinal , Iodides/chemistry , Mannitol/chemistry , Models, Animal , Parabens/chemistry , Perioperative Period , Propylene Glycol/chemistry , Sulfites/chemistry
14.
Water Environ Res ; 91(2): 165-174, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30735300

ABSTRACT

Clay material is used as a catalyst to degrade an organic pollutant. This study focused on the O-cresol oxidative degradation in aqueous solution by adding H2 O2 and Mont-Na. The catalytic tests showed a high catalytic activity of Mont-Na, which made it possible to achieve more than 84.6% conversion after 90 min of reaction time at 55°C in 23.2 mM H2 O2 . The pH value was found to be negatively correlated with the degradation rate of O-cresol. UV-Vis spectrophotometry revealed that the increase of degradation rate at low pH is related to the formation of 2-methylbenzoquinone as intermediate product. In addition, the content of iron in Mont-Na decreased after the catalytic test, bringing further evidence about the O-cresol catalytic oxidation. The mineralization of O-cresol is also confirmed by the different methods of characterization of Mont-Na after the catalytic oxidation test. The effect of the O-cresol oxidation catalyzed by natural clay is significant. PRACTITIONER POINTS: Algerian Montmorillonite-Na is used as a catalyst to degrade an organic pollutant: O-cresol. It shows a great potential for catalyst properties in the presence of the oxidizing reagent H2 O2 . It proved to be an effective means for the degradation of O-cresol contained in wastewaters.


Subject(s)
Clay/chemistry , Cresols/chemistry , Environmental Pollutants/chemistry , Hydrogen Peroxide/chemistry , Sodium/chemistry , Adsorption , Catalysis , Cresols/isolation & purification , Environmental Pollutants/isolation & purification , Hydrogen-Ion Concentration , Kinetics , Temperature , Water/chemistry
15.
Int J Mol Sci ; 20(18)2019 Sep 11.
Article in English | MEDLINE | ID: mdl-31514377

ABSTRACT

The lignin pyrolysis products generated by biomass combustion make an essential contribution to the formation of secondary organic aerosols (SOAs). The ozone-initiated oxidation of guaiacol, syringol and creosol, major constituents of biomass burning, were investigated theoretically by using the density functional theory (DFT) method at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. Six primary addition reaction pathways and further decomposition routes with corresponding thermodynamic values were proposed. The Criegee intermediates can be excited by small molecules, such as NOx, H2O in the atmosphere, and would further proceed via self-decomposition or isomerization. The most predominant product for ozonation of guaiacol is the monomethyl muconate (P1). At 295 K and atmospheric pressure, the rate constant is 1.10 × 10-19 cm3 molecule-1 s-1, which is lies a factor of 4 smaller than the previous experimental study. The branching ratios of the six channels are calculated based on corresponding rate coefficient. The present work mainly provides a more comprehensive and detailed theoretical research on the ozonation of methoxyphenol, which aspires to offer novel insights and reference for future experimental and theoretical work and control techniques of SOAs caused by lignin pyrolysis products.


Subject(s)
Biomass , Cresols/chemistry , Guaiacol/chemistry , Ozone/chemistry , Pyrogallol/analogs & derivatives , Atmosphere/chemistry , Kinetics , Molecular Conformation , Pyrogallol/chemistry
16.
Molecules ; 24(23)2019 Nov 27.
Article in English | MEDLINE | ID: mdl-31783502

ABSTRACT

Hawthorn seed can be used to produce various bioactive compounds through destructive distillation. In this study, an accurate and feasible analytical method based on a gas chromatography mass spectrometer (GC-MS) was developed for simultaneous determination of six major compounds (contributing to more than 3% in total peak area) in destructive distillation extracts of hawthorn seed collected at different temperatures ranging from 150 to 270 °C. Then, a broth microdilution method coupled with grey correlation analysis was engaged in the evaluation of their antimicrobial activities and the screening of primarily active compounds. Results indicate that the extract collected from 211 to 230 °C had the highest content of six major compounds (furfural, 2-methoxyphenol, 2-methoxy-4-methylphenol, 4-ethyl-2-methoxyphenol, 2,6-dimethoxyphenol, and 5-tertbutylpyrogallol) and the strongest antibacterial activity. Besides, 2,6-dimethoxyphenol was found to be a potential compound in inhibiting the growth of vaginitis pathogens. This study provided an optimum temperature for the destructive distillation of hawthorn seed, reducing the waste of energy, and saving the cost of production in the hawthorn industry.


Subject(s)
Anti-Bacterial Agents/pharmacology , Crataegus/chemistry , Gas Chromatography-Mass Spectrometry/methods , Seeds/chemistry , Anti-Bacterial Agents/chemistry , Cresols/chemistry , Cresols/isolation & purification , Cresols/pharmacology , Distillation/methods , Furaldehyde/chemistry , Furaldehyde/isolation & purification , Furaldehyde/pharmacology , Guaiacol/chemistry , Guaiacol/isolation & purification , Guaiacol/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Pyrogallol/analogs & derivatives , Pyrogallol/chemistry , Pyrogallol/isolation & purification , Pyrogallol/pharmacology
17.
Molecules ; 24(20)2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31618977

ABSTRACT

p-Cresyl sulfate is one of the bound uremic toxins whose level increases in the sera of patients with the severity of chronic kidney disease and is therefore used as a standard for clinical investigations. Our first attempts to obtain p-cresyl sulfate led exclusively to the product of sulfonation of the aromatic ring instead of sulfation on the OH moiety. Nevertheless, this initial discouraging result allowed us to handle both p-cresyl sulfate and 2-hydroxy-5-methylbenzenesulfonic acid obtained by different synthetic pathways. Interestingly, the comparison between the two isomers pointed out that the two molecules show the same fragmentation pattern and are indistinguishable by mass spectrometry. They cannot be separated on several commercially available columns. The only difference between the two compounds is a 10-fold higher ionization yield under negative ion electrospray ionization. NMR spectral studies definitely confirmed the different molecular structures. We present here an unambiguous biomimetic synthetic route for p-cresyl sulfate and the spectroscopic characterization of both the compounds by nuclear magnetic resonance and mass spectrometry.


Subject(s)
Biomarkers , Cresols/metabolism , Heart Diseases/metabolism , Kidney Diseases/metabolism , Sulfuric Acid Esters/metabolism , Toxins, Biological/metabolism , Chromatography, Liquid , Cresols/blood , Cresols/chemistry , Heart Diseases/blood , Heart Diseases/urine , Humans , Kidney Diseases/blood , Kidney Diseases/urine , Magnetic Resonance Spectroscopy , Molecular Structure , Sulfuric Acid Esters/blood , Sulfuric Acid Esters/chemistry , Tandem Mass Spectrometry , Toxins, Biological/blood , Toxins, Biological/chemistry
18.
Artif Organs ; 42(1): 88-93, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28703401

ABSTRACT

An accumulation of protein-bound uremic toxins (PBUTs) is one of major reasons for development of uremia-related complications. We examined the PBUT removal ability of a hexadecyl-immobilized cellulose bead (HICB)-containing column for patients undergoing hemodialysis. Adsorption of indoxyl sulfate (IS), a representative PBUT, to HICBs was examined in vitro. The HICB column was used in patients undergoing hemodialysis for direct hemoperfusion with a regular hemodialyzer. The serum IS, indole acetic acid (IAA), phenyl sulfate (PhS), and p-cresyl sulfate (PCS) levels were measured before and after passing the column. HICBs adsorbed protein-free (free) IS in a dose- and time-dependent manner in vitro (55.4 ± 1.4% adsorption of 1 millimolar, 251 µg/mL, IS for 1 h). In clinical studies, passing the HICB-containing column decreased the serum level of free IS, IAA, PhS, and PCS levels significantly (by 34.4 ± 30.0%, 34.8 ± 25.4%, 28.4 ± 18.0%, and 34.9 ± 22.1%, respectively), but not protein-bound toxins in maintenance hemodialysis patients. HICBs absorbed some amount of free PBUTs, but the clinical trial to use HICB column did not show effect to reduce serum PBUTs level in hemodialysis patients. Adsorption treatment by means of direct hemoperfusion with regular hemodialysis may become an attractive blood purification treatment to increase PBUT removal when more effective materials to adsorb PBUTs selectively will be developed.


Subject(s)
Cellulose/chemistry , Hemoperfusion/methods , Kidney Failure, Chronic/therapy , Renal Dialysis/methods , Toxins, Biological/chemistry , Uremia/therapy , Adsorption , Aged , Blood Proteins/metabolism , Cresols/blood , Cresols/chemistry , Cresols/metabolism , Cresols/toxicity , Feasibility Studies , Female , Hemoperfusion/instrumentation , Humans , Indican/blood , Indican/chemistry , Indican/metabolism , Indican/toxicity , Indoleacetic Acids/blood , Indoleacetic Acids/chemistry , Indoleacetic Acids/metabolism , Indoleacetic Acids/toxicity , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/complications , Male , Middle Aged , Porosity , Protein Binding , Renal Dialysis/instrumentation , Serum Albumin , Sulfuric Acid Esters/blood , Sulfuric Acid Esters/chemistry , Sulfuric Acid Esters/metabolism , Sulfuric Acid Esters/toxicity , Toxins, Biological/blood , Toxins, Biological/metabolism , Toxins, Biological/toxicity , Uremia/blood , Uremia/etiology
19.
J Environ Manage ; 213: 217-235, 2018 May 01.
Article in English | MEDLINE | ID: mdl-29500995

ABSTRACT

Flux decline due to membrane fouling by surfactant micelles is the major problem limiting the use of micellar enhanced ultrafiltration (MEUF) for the treatment of wastewater. Understanding of underlying mechanisms of membrane fouling, adsorption kinetics and adsorption isotherm are very important for the successful application of MEUF studies. In the present study, an unsteady state model considering sequential occurrence of complete pore blocking and gel layer formation was proposed for explaining flux decline behavior during rhamnolipid based MEUF for simultaneous removal of Cd+2 and p-cresol from aqueous solution under batch concentration mode. The model was developed based on the Hermia's complete pore blocking model and resistance-in-series model coupled with gel layer theory incorporating the effects of feed temperature, variation of viscosity and retentate concentration with time, and pressure dependent mass transfer coefficient. A good agreement between the experimental data and model predictions was demonstrated. The effects of operating conditions were found to have a significant effect on the flux decline behavior and onset of gel layer formation. The use of ultrafiltration membrane for the study of adsorption kinetics and adsorption isotherm was demonstrated. Kinetic studies disclosed that both Cd+2 and p-cresol adsorption was better described by the pseudo-second order model for both single and binary solution. The results of isotherm studies revealed that adsorption of both Cd+2 and p-cresol was spontaneous in nature and equilibrium data was best fitted by Langmuir model with the maximum adsorption capacity of RHL vesicles of 208.33 and 53.27 mg g-1 for Cd+2 and p-cresol, respectively at 299 K. The model parameters of membrane fouling, adsorption kinetics and adsorption isotherm evaluated in this study could be useful in designing and scale up of RHL based MEUF process.


Subject(s)
Cadmium/isolation & purification , Cresols/isolation & purification , Glycolipids/chemistry , Water Purification , Adsorption , Cadmium/chemistry , Cresols/chemistry , Kinetics , Micelles , Ultrafiltration , Wastewater , Water Pollutants, Chemical
20.
Molecules ; 23(7)2018 Jul 14.
Article in English | MEDLINE | ID: mdl-30011901

ABSTRACT

This article focuses on the antiradical activity of a number of 2,6-diisobornylphenol-porphyrin conjugates with various spacers between the porphyrin and phenolic fragments in the model reaction of ethylbenzene oxidation initiated by azoisobutyric acid dinitrile. The study has shown that the electronic effects of the groups directly related to the 2,6-diisobornylphenol fragment exert the predominant influence both on the reactivity of the phenolic hydroxyl group in interaction with free radicals and on the antiradical activity of the molecule as a whole. The antiradical activity of the molecule is generally less affected by the nature of the substituents in the porphyrin macrocycle, mainly due to a change in the stoichiometric inhibition coefficient in the presence of relatively easily oxidizable groups. It was found that the length of the spacer between the porphyrin and phenolic fragments does not affect the antiradical activity of the conjugate.


Subject(s)
Free Radical Scavengers/chemistry , Porphyrins/chemistry , Benzene Derivatives/chemistry , Camphanes/chemistry , Cresols/chemistry , Oxidation-Reduction
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