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Thiosemicarbazones (TSCs) with their modular character (thiosemicarbazides + carbonyl compound) allow broad variation of up to four substituents on the main R1R2C=N(1)–NH–C(S)–N(4)R3R4 core and are thus interesting tools for the formation of conjugates or the functionalization of nanoparticles (NPs). In this work, di-2-pyridyl ketone was introduced for the coordination of metals and 9-anthraldehyde for luminescence as R1 and R2 to TSCs. R3 and R4 substituents were varied for the formation of conjugates. Amino acids were introduced at the N4 position to produce [R1R2TSC–spacer–amino acid] conjugates. Further, functions such as phosphonic acid (R–P(O)(OH)2), D-glucose, o-hydroquinone, OH, and thiol (SH) were introduced at the N4 position producing [R1R2TSC–spacer–anchor group] conjugates for direct NP anchoring. Phenyl, cyclohexyl, benzyl, ethyl and methyl were used as spacer units. Both phenyl phosphonic acid TSC derivatives were bound on TiO2 NPs as a first example of direct NP anchoring. [R1R2TSC–spacer–end group] conjugates including OH, S–Bn (Bn = benzyl), NH–Boc (Boc = tert-butyloxycarbonyl), COOtBu, C≡CH, or N3 end groups were synthesized for potential covalent binding to functional molecules or functionalized NPs through amide, ester, or triazole functions. The synthesis of the thiosemicarbazides H2NNH–C(S)–NR3R4 starting from amines, including amino acids, SCCl2 or CS2, and hydrazine and their condensation with dipyridyl ketone and anthraldehyde led to 34 new TSC derivatives. They were synthesized in up to six steps with overall yields ranging from 10 to 85% and were characterized by a combination of nuclear magnetic resonance spectroscopy and mass spectrometry. UV-vis absorption and photoluminescence spectroscopy allowed us to easily trace the dipyridyl imine and anthracene chromophores. [ABSTRACT FROM AUTHOR]

The extraction of 1.09 × 10−2 Zr(IV) and 1.07 × 10−3 Nb(V) from their admixture solution was done using a phosphonic acid derivative (Ionquest 801 = IQ-801/kerosene). The calculated extraction constants for Zr(IV) and Nb(V) were found to be 17.1 × 103 M−3 and 1.1 × 103 M−1, respectively. The suggested extraction conditions were found to be (time =15–30 min, Organic: Aqueous ratio = 1, [HNO3] = 3 M, [IQ-801] = 0.015–0.02, and T = 25 ± 1. The calculated loading capacities per mole of IQ-801 were found to be 0.8 moles of Zr(IV) and 9 × 10−2 moles of Nb(V). According to McCabe-Thiele diagrams, 0.02 M IQ-801 can completely extract 1 × 10−2 M Zr(IV) and 1 × 10−3 M Nb(V) in just 2 stages. In the stripping process, about 99% Zr(IV) was stripped by stripping precipitation with 0.1 M oxalic acid and 1 M NaF, which also provides the best conditions for the separation of Nb(V) from Zr(IV). The highest separation was obtained using citric acid concentrations ranging from 0.25 to 4 M, oxalic acid concentrations ranging from 0.05 to 1 M, and sulfuric acid concentrations ranging from 1.5 to 3 M. A flow chart outlining the proposed technique steps for separating Zr(IV) and Nb(V) from an HNO3 solution using IQ-801 was suggested. [ABSTRACT FROM AUTHOR]

State‐of‐the‐art, high‐performance solar cells and light‐emitting diodes normally rely on tedious layer‐by‐layer sequential deposition of carrier transport layer and light‐absorbing/emitting layers, which is not cost‐effective. Several recent exciting works have demonstrated surprising breakthroughs in terms of simplified processing of these optoelectronic devices. Upon the incorporation of carbazole phosphonic acid molecules and their derivatives into precursor ink beforehand, charge‐selective contact could spontaneously self‐assemble at the buried interface between the conducting substrate and photoactive layer, which results in the construction of simplified‐structured devices that yield comparable optoelectronic performances to the conventionally fabricated devices with full architectures. Herein, the recent groundbreaking advancement of high‐performance optoelectronic devices fabricated via a convenient codeposition technique is summarized, with particular emphasis on elucidating the chemical mechanism of self‐assembly mode and highlighting the unique advantages of this strategy on crystallization regulation, targeted defect passivation, carrier dynamics modulation, and comprehensive device performance improvement. Finally, the associated challenges are critically discussed and the future research directions are insightfully proposed, which can revolutionize the pathway toward constructing highly efficient optoelectronic devices in a cost‐effective manner and setting forward to future commercialization. [ABSTRACT FROM AUTHOR]

Recent advances in visible light photocatalysis represent a significant stride towards sustainable catalytic chemistry. However, its successful implementation in fine chemical production remains challenging and requires careful optimization of available photocatalysts. Our work aims to structurally modify bioinspired porphyrin catalysts, addressing issues related to their laborious synthesis and low solubility, with the goal of increasing their efficiency and developing reusable catalytic systems. We have demonstrated the catalytic potential of readily available meso-tetrakis[4-(diethoxyphosphoryl)phenyl]porphyrins (M(TPPP)). Novel metal (Pd(II), Co(II) and In(III)) complexes with this ligand were prepared in good yields. These chromophores were characterized in solution using spectroscopic (NMR, UV-vis, fluorescence) and electrochemical methods. The introduction of phosphonate groups on the phenyl substituents of mesotetraphenylporphyrins (M(TPP)) improves solubility in polar organic solvents without significantly altering the photophysical properties and photostability of complexes. This structural modification also leads to easier reductions and harder oxidations of the macrocycle for all investigated complexes compared to the corresponding TPP derivatives. The free base porphyrin, zinc(II), palladium(II), and indium(III) complexes were studied as photocatalysts for oxidation of sulfides to sulfoxides using molecular oxygen as a terminal oxidant. Both dialkyl and alkyl aryl sulfides were quantitatively transformed into sulfoxides under blue LED irradiation in the acetonitrile-water mixture (10: 1 v/v) with a low loading (0.005-0.05 mol%) of porphyrin photocatalysts, where H2(TPPP) and Pd(TPPP) were found to be the most efficient. The reaction mechanism was studied using photoluminescence and EPR spectroscopies. Then, to access reusable catalysts, water-soluble derivatives bearing phosphonic acid groups, H2(TPPP-A) and Pd(TPPP-A), were prepared in high yields. These compounds were characterized using spectroscopic methods. Single-crystal X-ray diffraction analysis of Pd(TPPP-A) reveals that the complex forms a 3D hydrogen-bonded organic framework (HOF) in the solid state. Both H2(TPPP-A) and Pd(TPPP-A) were found to catalyze the photooxidation of sulfides by molecular oxygen in the acetonitrile-water mixture (1: 1 v/v), while only Pd(TPPP-A) resulted in selective production of sulfoxides. The complex Pd(TPPP-A) was easily recovered through extraction in the aqueous phase and successfully reused in five consecutive cycles of the sulfoxidation reaction. [ABSTRACT FROM AUTHOR]

We herein present for the first time the phosphylated (*) tetrapeptide (TP)-adduct GlyGluSer198*Ala generated from butyrylcholinesterase (BChE) with proteinase K excellently suited for the verification of exposure to toxic organophosphorus nerve agents (OPNA). Verification requires bioanalytical methods mandatory for toxicological and legal reasons. OPNA react with BChE by phosphonylation of the active site serine residue (Ser198) forming one of the major target protein adducts for verification. After its enzymatic cleavage with pepsin, the nonapeptide (NP) PheGlyGluSer*AlaGlyAlaAlaSer is typically produced as biomarker. Usually OPNA occur as racemic mixtures of phosphonic acid derivatives with the stereocenter at the phosphorus atom, e.g. (±)-VX. Both enantiomers react with BChE, but the adducted NP does not allow their chromatographic distinction. In contrast, the herein introduced TP-adducts appeared as two peaks when using a stationary reversed phase (1.8 µm) in micro-liquid chromatography–electrospray ionisation tandem-mass spectrometry (µLC–ESI MS/MS) analysis. These two peaks represent diastereomers of the (+)- and (−)-OPNA adducted to the peptide that comprises chiral L-amino acids exclusively. Concentration- and time-dependent effects of adduct formation with (±)-VX and its pure enantiomers (+)- and (−)-VX as well as with (±)-cyclosarin (GF) were investigated in detail characterising enantioselective adduct formation, stability, ageing and spontaneous reactivation. The method was also successfully applied to samples from a real case of pesticide poisoning as well as to samples of biomedical proficiency tests provided by the Organisation for the Prohibition of Chemical Weapons. [ABSTRACT FROM AUTHOR]

Many charged organic molecules behave as persistent and hazardous pollutants with harmful effects on human health and ecosystems. They are widely distributed related to their charged molecular structure that provides water solubility. In order to track the fate and behavior of such pollutants, charged dyes with specific absorption in the visible spectra serve as convenient model compounds. We provide a platform of smart adsorbers that efficiently remediate positively and negatively charged dyes (crystal violet and Amaranth) from water. Metal oxide nanoparticles serve as a core with an intrinsically large surface area. The surface potential was tuned towards positive or negative by decorating the cores with self‐assembled monolayers of dedicated long‐chained phosphonic acid derivatives. Selective remediation of the dyes was obtained with corresponding oppositely charged core‐shell nanoparticles. Mixed dye solution can be cleaned by a cascade approach or by applying both particle systems simultaneously. The removal efficiency was determined as a function of particle concentration via UV‐spectroscopy. The results of remediation experiments at different pH values and using superparamagnetic iron oxide nanoparticle cores lead to a simple process with recycling capability. [ABSTRACT FROM AUTHOR]

Ecto‐nucleotidase CD73 inhibits immune function by overproducing adenosine. A series of important studies have shown that CD73 is over‐expressed in many cancers, and CD73 inhibitors are promising drugs for cancer (immunotherapy). Here, we describe the structure optimization of a hit compound obtained through screening an in‐house chemical library, (3‐(4‐(3‐aminophenyl)‐1H‐1,2,3‐triazol‐1‐yl)phenyl‐(naphthalen‐1‐yl)methyl)phosphonic acid (1). A series of ((diphenylmethyl) phosphonic acid) derivatives were synthesized, and all target compounds were characterized by nuclear magnetic resonance (NMR) and mass spectrometry (MS). Then structure–activity relationship analysis using the in vitro enzymatic inhibition assay was performed, which led to the discovery of a number of compounds (11, 13, 14, 17, 19, 23, and 27) that exhibited greater inhibitory activity than the lead compound 1. Among them, the compounds 14 and 23, with p‐Cl and p‐ethyl substitution on the terminal phenyl ring respectively, showed the strongest inhibitory activity against CD73, with IC50 values of 2.35 and 2.55 μM respectively. And we believe that compounds 14 and 23 can serve as lead compounds for further research on specific CD73 inhibitors. [ABSTRACT FROM AUTHOR]

Beyond their CO2 emittance when burned as fuels, hydrocarbons (HCs) serve as omnipresent raw materials and commodities. No matter if as liquid oil spills or the endless amounts of plastic roaming the oceans, HCs behave as persistent pollutants with water as main carrier to distribute. Even if their general chemical structure [‐(CH2)n‐] is quite simple, the endless range of n leads to contaminations of different appearances and properties. A water remediation method based on superparamagnetic iron oxide nanoparticles (SPIONs) modified with self‐assembled monolayers of alkyl phosphonic acid derivatives is presented. These molecules enable the SPIONs to non‐covalently bind HCs, independently from the molecular weight, size and morphology. The attractive interaction is mainly based on hydrophobic and Coulomb interaction, which allows recycling of the SPIONs. The superparamagnetic core allows a simple magnetic collection and separation from the water phase which makes it a promising addition to wastewater treatment. Agglomerates of collected plastic "waste" even exhibit superior adsorption properties for crude oil, another hydrocarbon waste which gives these collected wastes a second life. This upcycling approach combined with presented recycling methods enables a complete recycling loop. [ABSTRACT FROM AUTHOR]

Here, surface‐enhanced Raman scattering (SERS) and tip‐enhanced Raman scattering (TERS) were used to characterize the selective adsorption of N‐substituted 4‐[(NH‐R)(phosphono)‐S‐methyl]phenylboronic acids on the surface of platinum nanoparticles (PtNPs) from an aqueous solution and from air. The nature of the interaction of the studied compounds with the PtNPs/H2O and PtNPs/air interfaces was discussed and compared. For this purpose, 4‐[(N‐anilino)(phosphono)‐S‐methyl]phenylboronic acid (1‐PBA‐PA) and its two analogs (2‐PBA‐PA and bis{1‐PBA‐PA}) as well as the PtNPs were synthesized in surfactant/ion‐free solution via a synthetic route that allows control of the size and morphology of the NPs. The positively charged PtNPs with a size of ~12 nm were characterized by ultraviolet–visible spectroscopy (UV–Vis), dynamic light scattering (DLS), scanning electron microscopy (SEM), and X‐ray powder diffraction (XRD). [ABSTRACT FROM AUTHOR]

The formation of mixed shell‐by‐shell (SbS) systems with tunable shell compositions is demonstrated by using molecular self‐assembly driven by chemical recognition motifs. Aluminum oxide nanoparticles (AlOx‐NPs) act as template surface for a self‐assembled monolayer (SAM) of either partially fluorinated fluoroalkyl or alkyl chained phosphonic acid derivatives or defined stoichiometric mixtures of those. By providing an equimolar mixture of corresponding fluoroalkyl and alkyl‐chained amphiphiles in water, the stoichiometry of underlaying mixed SAM on the NP‐surface preferentially directs the composition of the secondary self‐assembly. The composition of the shell‐by‐shell assemblies is studied by high performance liquid chromatography and fluorescence spectroscopy. The concept allows the formation of NP‐templated vesicle‐like bilayer structures, even consisting of orthogonal chain structures in tunable composition driven by chemical recognition and hydrophobic segregation. [ABSTRACT FROM AUTHOR]

Phosphonic acids represent a class of important structural units widely found in natural products and artificially synthesized functional molecules. Nature uses β-carbonyl phosphonic acid as a versatile building block to access structurally diverse phosphonic acid derivatives, which inspires a biomimetic way for chemists, however, it is limited by the detrimental tendency of C–P bond cleavages during chemical reactions. To address this challenge, we here developed an ionic-liquid-based data-driven screening (ILDDS), an approach that can comprehensively employ multifunctional effects of ionic liquids for discovering new reactivity, developing potent synthetic reactions, and even simplifying bioactivity evaluations. Using ILDDS, we repurposed the cycloaddition of β-carbonyl phosphonate and azide to synthesize triazolyl phosphonates that usually produced phosphonate-leaving products under the traditional conditions. And then, the repurposed cycloaddition reaction allows the access of triazolyl phosphonates bearing various substituents under mild conditions. Furthermore, an integrative workflow combining modular and combinational syntheses, simple purification, and in situ bioactivity evaluation can be de novo designed and implemented in a high throughput way, finally leading to fast acquirements of phosphonate compounds for inhibiting the growth of Rhizoctonia solani. [ABSTRACT FROM AUTHOR]

In an attempt to obtain the modified and novel insecticides with low human toxicity, a series of novel mono-, bis-, and tetraphosphonic acid derivatives were designed and characterized by infrared, 1H, 13C, and 31P NMR spectroscopy and X-ray crystallography. The inhibitory effects of the synthesized compounds were evaluated using the in vitro Ellman method on human and insect acetylcholinesterase (AChE). Some of these compounds, which had low human and high insect toxicity, were chosen to assess the killing effects (in vivo) on third larval instar of elm leaf beetle (X. luteola). In vivo and in vitro evidence has revealed that bisphosphonic acids, containing hydrophobic systems, have a good selectivity of insect AChE inhibition. In the present study, docking results showed that bisphosphonic acids had lower binding energy and higher inhibition compared with tetraphosphonic acids due to the type of their topology and the ability of their hydrogen to interact with the catalytic triad (the main active site of the enzyme). Additionally, the QSAR results demonstrated that the major effecting factors on the insecticidal activity of the subject compounds are the hydrophobicity, size, shape, and ability to form a hydrogen bond. The present study can be helpful in the development of new insecticides. [ABSTRACT FROM AUTHOR]

A series of phosphonic acid and bisphosphoramidate derivatives were synthesized and characterized. The bioactivities against the fungal pathogen Macrophomina phaseolina and human acetylcholinesterase AChE enzyme were studied using QSAR based on multiple linear regression. L17, with (p-Cl–C6H4–NH) (p-Cl–C6H4)C(H)P(O)(OC2H5)2 skeleton, demonstrated a great mortality on the M. phaseolina mycelial growth by 83% inhibition at 150 mg/L; the other tested derivative showed moderate to weak antifungal activity against the fungus. QSAR model based on the GA-MLR method revealed the importance of 3D descriptors (De, Mor18e, H8m, and Mor30p) on the antifungal activity. It showed good capability in predicting the fungicidal activity of the studied molecules. Another derivative, L5, with (m-CH3–NC5H4–NH)(m-CH3–C6H4)C(H)P(O)(OCH3)2 skeleton displays the most potent anti-AChE activity. The electronic parameters, ΔEL-H, and ELUMO, have the highest contribution of human AChE. The authors suggest that these models could be usefully employed in designing more effective crop protection compounds without side effects on non-target organisms. [ABSTRACT FROM AUTHOR]

Crystalline polymer/single-walled carbon nanotube (SWCNT) nanocomposites were prepared using organo-modified SWCNTs with surface modification by long-chain phosphonic acid derivatives having bidentate bonds, resulting in excellent heat resistance properties. Surface modification with a long-chain phosphonate is non-desorbing, has a high desorption suppression temperature and can improve miscibility with matrix polymers by changing the other end of the functional group in various ways. In addition, since organo-SWCNTs showed amphiphilic properties when introducing a modified chain after hydrophilization, their structure and morphology could be characterized by the method of organized molecular films. The utilization of phosphonic acid derivatives containing fluorocarbon chains endowed SWCNTs with remarkable cohesive properties in phase-separable crystalline fluoropolymers to achieve polymer-based nanocomposite formation. Fluorinated SWCNTs could be easily introduced into fluoropolymers via a simple melt-compounding method. The crystalline fluoropolymer/fluorocarbon-modified SWCNT nanocomposite showed clear improvement in crystallization temperature compared with the matrix polymer. Simultaneously with the improvement in the crystallization temperature, it was confirmed that the crystallite size was increased, the lamella was thickened, the mechanical properties were improved, and the pyrolysis temperature was increased. These enhancements of the physical properties seem to be the result of the interaction between the modified-chain end and the polymer ends, and it was predicted that heterogeneous nucleation was induced by the nucleation effect. [ABSTRACT FROM AUTHOR]

A new series of shell‐by‐shell (SbS)‐functionalized Al2O3 nanoparticles (NPs) containing a perylene core in the organic interlayer as a fluorescence marker is introduced. Initially, the NPs were functionalized with both, a fluorescent perylene phosphonic acid derivative, together with the lipophilic hexadecylphosphonic acid or the fluorophilic (1 H,1 H,2 H,2H‐perfluorodecyl)phosphonic acid. The lipophilic first‐shell functionalized NPs were further implemented with amphiphiles built of aliphatic chains and polar head‐groups. However, the fluorophilic NPs were combined with amphiphiles consisting of fluorocarbon tails and polar head‐groups. Depending on the nature of the combined phosphonic acids and the amphiphiles, tuning of the perylene fluorescence can be accomplished due variations of supramolecular organization with the shell interface. Because the SbS‐functionalized NPs dispose excellent dispersibility in water and in biological media, two sorts of NPs with different surface properties were tested with respect to biological fluorescent imaging applications. Depending on the agglomeration of the NPs, the cellular uptake differs. The uptake of larger agglomerates is facilitated by endocytosis, whereas individualized NPs cross directly the cellular membrane. Also, the larger agglomerates were preferentially incorporated by all tested cells. [ABSTRACT FROM AUTHOR]

A convergent approach for the incorporation of tetrafluoroaryl phosphonate moieties into cyclic triphosphazenes and linear phosphazene resins is described. Our high yield procedure is based on the treatment of chlorinated poly‐ and cyclotriphosphazenes with p‐HO(C6F4)P(O)(OR)2 (R = Me, Et) in the presence of potassium carbonate. Characterization of the modified cyclotriphosphazenes was accomplished by NMR and IR spectroscopy as well as by mass spectrometry. Similarly, a phosphazene resin decorated with phosphonic esters is characterized by NMR and IR spectra and GPC. Exchange of the ethyl group by a trimethylsilyl group in the novel phosphazene derivatives was effected by the reaction with trimethylsilyl bromide. The resulting silyl phosphonates were converted into the corresponding phosphonic acids by exposure to an excess of methanol. Proton conductivities of the novel phosphonic acid derivatives of poly‐ and cyclotriphosphazenes were studied by electrochemical impedance spectroscopy under anhydrous conditions. [ABSTRACT FROM AUTHOR]

Two triazole derivatives with phosphonic acid as pendent group, namely [3-(4-phenyl-[1–3]triazol-1-yl)-propyl]-phosphonicaciddiethylester (PTP) and [3-[4-(4-dimethylamino-phenyl)-[1–3]triazol-1-yl]-propyl]-phosphonic acid diethylester (DMPTP) were synthesized and fully characterized using NMR spectroscopy, Mass spectrometry, Infra-Red (FT-IR) spectroscopy and elemental analysis. The synthesized multifunctional heterocycles were investigated to inhibit the corrosion of mild steel in acidic solution HCl (1 M) by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) and weight loss measurements. The results of the different corrosion measurement techniques are in good agreement. The potentiodynamic polarization analysis shows that the PTP and DMPTP derivatives are mixed-type inhibitors. In addition, EIS measurements were used to simulate the corrosion inhibition process by using a suitable equivalent circuit. The thermodynamic and kinetic parameters obtained demonstrated that both inhibitors adsorb to the surface of mild steel according to the Langmuir model's isotherm. A layer adsorbed onto the surface of the mild steel has been confirmed by FT-IR, scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. Moreover, Density Functional Theory (DFT) analysis and Molecular Dynamics simulations (MD) have been carried out, the computational results agreeing with the experimental ones. [ABSTRACT FROM AUTHOR]

Based on propargyl alcohol esters, new derivatives of phosphorous and phosphonic acids of the acetylene series of various structures were synthesized (10 compounds). The prepared substances (6 compounds) significantly inhibit the corrosion of 08kp low-carbon steel in 5 M HCl (T = 20–60°C). The protective effect of these inhibitors increases with a rise in their content in solution and with increasing temperature. The strongest inhibition of steel corrosion is provided by phosphonic acid esters containing an alcohol group in their composition. For the synthesized corrosion inhibitors, an adsorption-polymerization mechanism of action is assumed, which is evidenced by the enhancement of the protective effect of these compounds with increasing temperature. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of experiments on the sorption characteristics of phosphorus-containing ion exchangers Purolite MTS9580 (functional group ? derivatives of phosphonic acid) and Lewatit TP260 (functional group ? aminomethylphosphonic acid) on scandium. Using the method of low-temperature nitrogen adsorption, structural characteristics of selected ion exchangers Purolite MTS9580 and Lewatit TP260 respectively were measured. The specific surface of Purolite MTS9580 and Lewatit TP260 ion exchangers was measured as 5.1 and 4.5 m2/g, respectively. The obtained values indicate the presence of a macroporous structure in the ion exchangers. Experiments were carried out on the sorption of scandium and critical impurities in a static mode and dynamic mode while varying the acidity of the initial mother liquor of the sorption of uranium. Comparison of scandium sorption from pre-acidified uranium sorption mother liquor with Lewatit TP260 and Purolite MTS9580 ion exchangers showed an advantage for MTS9580 resin. The MTS9580 resin had an exchange capacity of 200 mg Sc/dm3 versus 59.7 mg Sc/dm3 for TP260. The dynamic exchange capacity of Purolite MTS9580 is much lower in relation to harmful impurities as Al, Fe, Ca, etc. [ABSTRACT FROM AUTHOR]

Polymer‐based nanohybrid materials were created using sustainable sepiolite clay composed from ubiquitous elements. Although sepiolite is generally recognized as a fibrous natural clay mineral, it turned out to be an acicular microcrystal because of the organo‐modification of the outermost surface. Surface modification was performed using phosphonic acid derivatives containing hydrocarbon chains or fluorocarbon chains. Formation of a bidentate bond enhanced the desorption temperature and made nanocomposite preparation possible by melt compounding with polymers having a high melting point. As a result of organo‐modification, amphiphilic sepiolite was obtained, and nanodispersion in an organic solvent was achieved. This technology was useful for detailed evaluation of sepiolite morphology. The nanocomposite of crystalline polymers/organo‐modified sepiolites achieved uniform dispersion of these nanofillers in the matrix polymer. The introduction of 1 wt% nanofillers did not impair the transparency of the matrix polymer. As a result, a lamellae structure of the polymer developed, the crystallinity increased, and the mechanical properties improved. In addition, the crystallization temperature was improved, indicating that organo‐modified sepiolites may act as a nucleating agent. It was found that sepiolite nanofiller with a highly aggregated tendency can achieve a well‐nanodispersed state, even in phase‐separable fluoropolymers, by applying fluorocarbon modification. POLYM. ENG. SCI., 60:541–552, 2020. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A practical method for synthesizing chiral α‐amino phosphonic acid derivatives was developed. Readily available and stable N‐o‐nitrophenylsulfenyl (Nps) imino phosphonate was utilized as a substrate for a highly enantioselective Friedel–Crafts‐type addition of indole or pyrrole nucleophiles catalyzed by chiral phosphoric acid. The resulting adduct was easily converted into N‐9‐fluorenylmethyloxycarbonyl (Fmoc) amino phosphonic acid, which is useful for synthesizing peptides containing an amino phosphonic acid. [ABSTRACT FROM AUTHOR]

Abstract A series of new aminophosphonate and phosphonic acid derivatives of hexahydroquinoxalin-2(1 H)-ones and tetrahydroquinoxalin-2(1 H)-ones were synthesised via hydrophosphonylation of the corresponding bicyclic imines with various dialkyl or diaryl H -phosphonates, H -phosphinates or H -phosphine oxides as phosphorus nucleophiles. The utility of the obtained compounds was demonstrated by their application as a source of phosphonate carbanion in the Horner-Wadsworth-Emmons (HWE) reaction leading to new bicyclic amines with an exocyclic, and unexpectedly, also endocyclic double bond depending on the structure of the aldehyde used. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Fosfomycin (C3H7O4P) is a phosphonic acid derivative representing an epoxide class of antibiotics. The drug is a re-emerging bactericidal antibiotic with a wide range of actions against several Gram-positive and Gram-negative bacteria. Among the existing antibacterial agents, fosfomycin has the lowest molecular weight (138 Da), which is not structurally associated with other classes of antibiotics. In intensive care unit (ICU) patients, severe soft tissue infections (STIs) may lead to serious life-threatening problems, and therefore, appropriate antibiotic therapy and often intensive care management (ICM) coupled with surgical intervention are necessary. Fosfomycin is an antibiotic primarily utilized for the treatment of STIs in ICUs. Recently, fosfomycin has attracted renewed interest for the treatment of serious systemic infections caused by multidrug-resistant Enterobacteriaceae. In some countries, intravenous fosfomycin has been prescribed for various serious systemic infections, such as acute osteomyelitis, nosocomial lower respiratory tract infections, complicated urinary tract infections, bacterial meningitis, and bacteremia. Administration of intravenous fosfomycin can result in a sufficient concentration of the drug at different body regions. Dose modification is not required in hepatic deficiency because fosfomycin is not subjected to enterohepatic circulation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Synthesis of fluorinated iminophosphonates with N-(α-phenylethyl) stereodirecting group was developed. • The first representatives of enantiopure fluoroalkylated α-aminophosphonates were prepared. • The synthesis is based on the diastereoselective reduction of α-iminophosphonates. • Synthesis of novel chiral synthon, (R)-N- tert -butylsulfinylimine of tetrafluoropropanal, was developed. • 31P, 19F NMR distinctions of diastereomeric aminophosphonates allow determination of their absolute configurations. Abstract The asymmetric synthesis of biorelevant aminophosphonates and aminophosphonic acids bearing trifluoromethyl, tetrafluoroethyl, perfluoropropyl or chlorodifluoromethyl group in the α-position to phosphonyl group is developed. Diastereoselective reduction of α-(poly)fluoroalkylated iminophosphonates, bearing stereodirecting α-phenylethyl group at the nitrogen atom, with sodium borohydride produces diastereomeric N-(α-phenylethyl) polyfluoroalkylphosphonates, readily separated by column chromatography. The highly stereoselective reaction of (R)-N-tert-butylsulfinylimine of tetrafluoropropanal with generated in situ diethyltrimethysilylphosphite leads to (R , R)-N-(tert-butylsulfinyl)tetrafluopropylphosphonate. Sequential N- and O-deprotection affords enantiomerically pure polyfluoroalkylphosphonate and aminophosphonic acids. The presence of α-phenylethyl group at the nitrogen atom allows easy determination of absolute configuration of the newly formed stereogenic center by the 31P,19F NMR method. [ABSTRACT FROM AUTHOR]

A convenient methodology for the synthesis of previously unreported (1H-indol-6-yl)phosphonic acid derivatives has been described. Reaction of (4-methyl-3,5-dinitrophenyl)phosphonates with dimethylformamide dimethyl acetal leads to the respective enamines that can be readily converted into indoles by the Batcho-Leimgruber synthetic protocol. Proper choice of reducing agent for the reductive cyclization of intermediate enamines allows to selectively obtain (4-nitro-1H-indol-6-yl)- and (4-amino-1H-indol-6-yl)phosphonates. [ABSTRACT FROM AUTHOR]

The separation of Y(III) from Eu(III) using a hollow fiber-supported liquid membrane with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (EHPNA) as an extractant was studied. The effects of HCl and metal concentrations in the feed solution, the EHPNA concentration in the membrane, and the HCl concentration in the stripping solution on the initial fluxes of the two metals and the separation factor were investigated. The optimum conditions for selective recovery of Y(III) from an equimolar solution of Y(III) and Eu(III) chlorides (0.001 mol L−1 each) were as follows: HCl concentration in the feed solution, 0.1 mol L−1; EHPNA dimer concentration in the organic phase in the membrane, 0.1 mol L−1; and HCl concentration in the stripping solution, 4 mol L−1. Under these conditions, complete Y(III) extraction was achieved after 1 ks of operation, and the Y(III) purity in the stripping solution was 84%. [ABSTRACT FROM AUTHOR]

Inorganic-organic hybrid membranes consisting of an aliphatic backbone and amorphous TiO 2 nanoparticles (NPs) were synthesized from tetraallyloxytitanium and phosphonic acid methacrylate via a simple copolymerization-hydrolysis method. Tetraallyoxytitanium (TAT) was copolymerized with 2-hydroxyethyl methacrylate acid phosphate (HEMAP), and then hydrolyzed, yielding inorganic-organic hybrid composites. IR and 13 C NMR spectroscopy confirmed the formation of the inorganic-organic hybrid structure. TEM and SAXS showed that amorphous TiO 2 NPs were dispersed in the polymer matrix. The membranes exhibited good thermal stability up to 180 °C. The aliphatic chains of the methacrylate derivative dispersed with TiO 2 NPs improved the mechanical properties of the membranes. The tensile modulus of the HEMAP/TAT membrane with a composition of 95:5 was 505 MPa. The conductivity of the 95:5 membranes was 4.1 × 10 -2 S cm -1 at 130 °C and 100% relative humidity (RH), while it was 4.7 × 10 -4 S cm -1 at 130 °C and 19.3% RH. The peak power of the 95:5 membrane was 4.8 mW/cm 2 at 140 °C and 30% RH. The cell utilizing the hybrid membrane was operated at 140 °C and 30% RH for 72 h without any drop in cell voltage. [ABSTRACT FROM AUTHOR]

1-Hydroxy-3-(5,7-dimethyl-2-oxo-1,2-dihydro-1,8-naphthyridin-1-yl)propylidenebisphosphonic acid has been synthesized. The structure of the acid and its precursors synthesized for the first time, 3-(5,7-dimethyl-2-oxo-1,2-dihydro-1,8-naphthyridin-1-yl)propionic acid and the corresponding methyl ester, in the solid state and in the DMSO solution has been elucidated by means of vibrational (IR and Raman) and multinuclear (1H, 13C, and 31P) NMR spectroscopy. [ABSTRACT FROM AUTHOR]

A modified method for the preparation of 2,5-diamino-5,5-diphosphonovaleric acid (DADP5) has been developed in the search for new synthetically available organic ligands to produce 188Re radiopharmaceuticals with an increased accumulation in the bone tissue. Interaction of the obtained acid with 188Re was studied by radio-TLC. An optimal system for separating unbound 188Re and labeled complex in a yield of at least 95% was found. The biological distribution of 188Re-DADP5 was studied based on direct radiometric data. The osteotropicity of 188Re-DADP5 and its increased accumulation in bone fracture sites, which represent oncological pathology models, was detected at a level comparable to known radiopharmaceuticals. [ABSTRACT FROM AUTHOR]

The results of systematic studies demonstrated wide possibilities of the three-component Kabachnik-Fields and two-component Pudovik reactions catalyzed by metal phthalocyanines in the synthesis of structurally diverse α-aminophosphonates. Extension of this catalytic method to the synthesis α-aminophosphinates gave rise to a series of α-amino- and α-hydrazinophosphinates based on biogenic amino acids. A number of α-hydrazinophosphonates showed a good antioxidant activity. [ABSTRACT FROM AUTHOR]

Among the electrolyte membranes for proton conduction in hydrogen production systems and fuel cells, phosphonic acid-based membranes are promising because of their advantage as good proton conductors in anhydrous medium which allows their use in systems operating at high temperature (80–150 °C) which is not the case of sulfonic acid-based ones such as the well-known Nafion® commercial membrane. In this study, a plasma polymerization process using a continuous or pulsed glow discharge has been implemented to prepare original Plasma Enhanced Chemical Vapor Deposition (PECVD also called plasma polymerization) phosphonic acid-based membranes using dimethyl allylphosphonate as a single precursor. The structural and proton transport properties of such membranes have been correlated with the plasma parameters in the deposition of films. The membranes prepared by pulsed plasma deposition method exhibit a better proton conductivity than that of membranes prepared by continuous plasma deposition method, in direct relation with their specific structural properties. The optimal plasma membrane, obtained in a pulsed 100 W plasma discharge, has shown specific resistance to proton conduction twice less than Nafion® 212 one which is great for the final applications of such membrane. [ABSTRACT FROM AUTHOR]

Metal-organophosphonates can be a superior alternative to the widely-explored carboxylate based metal organic frameworks (MOFs) as they exhibit better heat resistance and air sensitivity. However, due to the highly diverse binding modes of the metal-organophosphonate compounds and limited number of arylphosphonate linkers, it has been a very difficult task to create predictable extended and porous frameworks in this system. In 80s, 90s and 2000s, the literature of metal-organophosphonate chemistry were dominated by aliphatic linkers and highly dense pillared layered structures. Only recently rigid and structurally directing aromatic organophosphonates have been synthesized and employed to create porous frameworks. With metal-arylphosphonate chemistry still being an emerging field there is an urgent need to provide an overview of published arylphosphonates, their metal complexes and properties. Herein, we summarize the known metal-arylphosphonates based on their geometrical structures and number of phosphonate linkers around the aryl scaffold. The first part of the review summarizes the linear ditopic arylphosphonate linkers, the second part summarizes the trigonal planar geometries and the effect of opening the distance between the phosphonate linkers on the porosity. The third chapter focuses on tetratopic organophosphonate linkers with two-dimensional square planar geometries and geometries opening to three-dimensions. In the final chapter, miscellaneous multitopic organophosphonate linkers are presented. The review article not only summarizes arylphosphonic acids but also the their related arylphosphonate monoesters and diesters. In addition to structural chemistry, each of the chapters presented in the review article also summarize catalytic, sorptive and proton conductivity properties of published metal organophosphonates. [ABSTRACT FROM AUTHOR]

The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. DC is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ 13 C analysis to be used as a fingerprinting tool in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. We demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a significant isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool. [ABSTRACT FROM AUTHOR]

The reaction of aqueous suspension of finely dispersed iron with one equivalent of (1-hydroxyethylidene) diphosphonic acid (H4L) results in poorly soluble iron(II) (1-hydroxyethylidene)diphosphate FeH2L·H2O. The reaction with two equivalents of the acid gives a water-soluble compound Fe(H3L)2, which undergoes disproportionation up to FeH2L·H2O and H4L. The reaction of a FeH2L·H2O aqueous suspension with an organic amine results in the dissolution of the complex. Heating the FeH2L·H2O aqueous suspension in a pressure reactor at 150°C in the presence of KF catalytic amounts causes the formation of a new crystal phase and X-ray-amorphous admixtures. [ABSTRACT FROM AUTHOR]

The fluorescence detection of di-phosphonic acid and mono-phosphonic acid derivatives using the anthracene-based diamidine 1 has been investigated. The diamidine 1 forms 1:1 and 1:2 complexes with the di-phosphonic acid and mono-phosphonic acid derivatives, respectively, and showed a blue fluorescence ( λ em = 432–442 nm) in a DMSO solution. The formation of amidinium-phosphonate (complex formation) and dissociated amidinum ( λ em = 468 nm as a broad band) were distinguished by the difference in the fluorescence wavelength, and confirmed by DOSY NMR spectroscopy and TD-DFT calculations. The formation of a 1:2 complex with diamidine 1 and methylphosphonic acid having additional intermolecular hydrogen-bonding between the methylphosphonic acids is proposed. [ABSTRACT FROM AUTHOR]

Porous chitosan composites using CO 2 dissolution procedure and including water soluble N-propylphosphonic chitosan derivative (p-CHI) were obtained and characterized. In contrast to the control material, composites containing modified chitosan distinguished by a rapid moisture absorption and good adhesion to the skin. The FTIR analysis confirmed the presence of propylphosphonic group in the structure of the polymer. The porosity of the materials was in the range 55–77% and decreased with increasong amount of modified chitosan in materials. Solubility of composites was dependent on the content of p-CHI in scaffolds (40%, 25% and 15%) and reached values 11%, 9% and 6,5%, respectively. The values of other parameters like swelling degree (30 g/g) good antioxidant and antimicrobial properties (almost 100% reduction of S.aureus, E.coli and C. albicans growth) and low in vitro cytotoxicity against fibroblasts were highly advantageous for possible biomedical applications of the composites. [ABSTRACT FROM AUTHOR]

A homologous series of mesogenic phosphonic acid derivatives ( C n PA ) were synthesized through the Michaelis-Becker reaction. Chemical structures of the derivatives were characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy and high-resolution mass spectrometry. Differential scanning calorimetry measurements and polarizing optical microscopic observations indicated that C n PA exhibited smectic A and nematic phases at intermediate temperatures (119–196 °C). Temperature-dependent X-ray diffraction measurements suggested that smectic C n PA formed a bilayer architecture in which phosphonic acid moieties aggregated into lamellar arrays. Electrochemical impedance spectrum measurements using indium tin oxide (ITO) electrodes revealed that the liquid crystal phases favored anhydrous proton conduction of the phosphonic acid derivatives and the proton conductivities on the order of 10 −4 S cm −1 were achieved. [ABSTRACT FROM AUTHOR]

Efficient synthesis of novel 6-(2-bromo-2-methyl propanoyloxy)hexyl phosphonic acid, dodecane di-phosphonic acid, 6-(thiophene-3-carbonyloxy)hexyl phosphonic acid, octadecyl phosphonic acid and such other derivatives are reported here. These derivatives have a potential application as tethers to nanoparticle surfaces that can promote efficient electron transfer process in solar energy conversion. DOI: http://dx.doi.org/10.4314/bcse.v28i1.17

pH-Potentiometric method in combination with mathematical modeling was used to study the system manganese(ii)—gadolinium(iii)—1-hydroxyethylidenediphosphonic acid (HEDP, H4L). When both cations simultaneously are present in the solution, the accumulation of heteronuclear forms with the ratio of Gd: Mn: HEDP equal to 1: 1: 1, 1: 1: 2, and 1: 1: 3 was observed already in the strongly acidic pH region, while from homonuclear forms only five complexes were detected in the solution, namely, MnL26-, GdH4L2-, GdH2L+, KGd2HL2↓, and K3Gd2L2(OH)↓. It was concluded that heteronuclear complexes are much stronger and replace homonuclear forms in solution. [ABSTRACT FROM AUTHOR]

The first enantioselective synthesis of chiral heterocyclic α-amino phosphonates by nucleophilic dearomatization of quinolines and pyridines using an anion-binding organocatalysis approach is described. Chiral tetrakistriazoles were employed as efficient hydrogen-bond donor catalysts by forming a chiral close ion-pair with the in situ formed N-acyl salts and 2,2,2-trichlorethoxycarbonyl chloride (TrocCl). The ion-pair was subsequently treated with various phosphorus nucleophiles, such as silyl-protected dialkyl- and trialkylphosphites. Thus, the corresponding products were obtained in complete or high regioselectivities and up to 97:3 e.r. for quinolines or up to 89:11 e.r. for the more challenging pyridine substrates. This method allows for rapid access to substituted chiral cyclic α-amino phosphonates, which can be easily transformed into phosphonic acid derivatives. [ABSTRACT FROM AUTHOR]

The surface of titanium nitride (TiN) contains, in addition to nitride compounds, a certain amount of native oxide. This oxide allows the functionalization of TiN with amine-terminated groups through spontaneous self-assembly of aminoethylphosphonic acid. However, real industrial applications of titanium nitride, particularly for microelectronics and electrochemistry, require the development of efficient methods to improve the aminoethylphosphonate loading while preserving the main intrinsic characteristics of the TiN substrate. It is demonstrated that surface pretreatment, by either electrochemical anodization or cleaning in H2O2:HCl:H2O mixture, considerably enhances the phosphonic loading. This is the first report on mild oxidation of TiN surface using an acidic peroxide mixture. This electrochemical-assisted method does not require any electrochemical equipment, and works through simple immersion of the TiN surface in the cleaning solution at room temperature. Moreover, cleaning in this solution leads to a significantly increased quantity of the grafted phosphonate groups via uniform hydroxylation of the entire surface, without altering the behavior of the pristine TiN. The electrochemical anodization technique, which results in quasicomplete conversion of surface TiN compounds to TiO2 under our working conditions, needs further fundamental investigation towards incorporation of oxygen into the TiN lattice. [ABSTRACT FROM AUTHOR]

The reaction of an aqueous suspension of basic cobalt carbonate CoCO·4Co(OH)·3HO with equimolar amount or two-fold excess of 1-hydroxyethylydenediphosphonic acid (HL) has yielded crystalline CoHL and amorphous Co(HL) products, respectively. The interaction of poorly soluble CoHL complex with 2-aminoethanol has resulted in the formation of amorphous water-soluble CoHL·HNCHCHOH·6НО complex; the latter loses 5 water molecules at heating and is converted into CoHL·HNCHCHOH·НО. The study of agrochemical effects of Co(HL) and CoHL·HNCHCHOH·6НО has revealed their advantage over the conventional salt form (cobalt sulfate) reflected in the reduced phytotoxicity of the element. The prepared compound containing 2-aminoethanol (solubility promotor) has revealed better performance. [ABSTRACT FROM AUTHOR]

A new aminophosphonic derivative was synthesized and characterized by UV-vis, IR, 1 H NMR, 13 C NMR and MS spectroscopic methods. Its inhibitive action on the carbon steel corrosion in a 0.5 M H 2 SO 4 solution was studied by polarization curves and electrochemical impedance spectroscopy (EIS). The results indicated that the synthesized compound is an efficient mixed-type inhibitor and its inhibition efficiency increased with increasing the inhibitor concentration. The adsorption of the inhibitor on the carbon steel surface obeys Langmuir isotherm and the thermodynamic parameters were obtained. The surfaces of carbon steel after exposing to test solutions were examined by atomic force microscopy (AFM). The quantum chemical parameters were calculated in gas and aqueous phases using the density functional method (DFT). The interaction between the inhibitor and Fe (100) surface were performed by molecular dynamic simulations. [ABSTRACT FROM AUTHOR]

A series of novel and readily accessible N -benzylated ( N -arylcarbamoyl)alkylphosphonate esters and related compounds have been prepared as potential antimalarial agents. Bioassays reveal that some of these compounds exhibit promising activity against Plasmodium falciparum , and exhibit no significant growth inhibition of HeLa cells. [ABSTRACT FROM AUTHOR]

In this paper, we give an overview of the role of molecular dynamics (MD) simulations in the field of proton exchange membranes. We focus on structural and dynamical findings regarding the topology of hydrogen bond networks and proton diffusion. On the one hand, findings about water-containing polymer electrolyte membrane fuel cell materials, such as Nafion and liquid containing pore materials are discussed. On the other hand, proton conduction in water-free systems is elucidated. Here, the focus lies on phosphonic acids, which possess a rigid structure, and polymers based on phosphonic acids. [ABSTRACT FROM AUTHOR]

Scale formation from calcium carbonate deposition is a major drawback in many industrial facilities, including oil and gas industry, leading to obstruction problems then causing productivity reduction and economic loss. Several anti-scalant formulations, known as inhibitors, are used to control CaCO 3 deposition. The evaluation of inhibitors performance is a time-consuming challenge. In the present work a fast approach for evaluation of inhibitor towards calcium carbonate scale controlling is proposed based on continuous pH measurement under jar test condition. Two commercial inhibitors, phosphino polycarboxylic acid (PPCA), usually regarded as a nucleation inhibitor, and diethylenetriamine pentamethylene phosphonic acid (DETPMP), normally considered a growth inhibitor, were evaluated. It was possible to assess their efficiency at same concentration level (5.0 ppm), and DETPMP was the one presenting a better performance at the investigated conditions. The main mechanism of action of each inhibitor was also recognized by this methodology. [ABSTRACT FROM AUTHOR]

The efficiency of removing U and Th from a liquid organic scintillator based on linear alkylbenzene (LAB) by stripping with a 0.02 M aqueous solution of aminomethylenediphosphonic acid and by sorption on aluminum oxide and silica gel was studied. A procedure was developed for purification of scintillation additives (2,5-diphenyloxazole, 2-biphenyl-5-phenyloxazole, p-terphenyl) to remove K. [ABSTRACT FROM AUTHOR]