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An enantioselective tandem sequence that comprises a cycloaromatization process followed by an intramolecular desymmetrizing Friedel‐Crafts alkylation of functionalized cyclohexadienones has been accomplished. The process takes place in good yields (65–95%), with excellent diastereoselectivity (>20:1) and enantiomeric ratios up to 90.5:9.5 in the presence of (R)‐BINOL‐derived N‐triflyl phosphoramides, and it gains access to a family of pyrrolo[2,1‐a]isoquinoline derivatives in a simple manner, with the simultaneous generation of two vicinal stereocenters, one of them a tetrasubstituted carbon stereocenter. [ABSTRACT FROM AUTHOR]

Waterborne polyurethane (WPU), which is a novel and environmentally friendly variety of polyurethane, replaces organic solvents with water. It has been extensively utilized in diverse fields encompassing coatings, textile finishing, building decoration, adhesives, plastic chemistry, and others. However, WPU is inherently flammable and releases a significant amount of smoke production during the combustion process. This research presents an original fire‐resistant Waterborne Polyurethane (WPU) with a newly‐integrated flame‐retardant component comprising a triazine phosphoramidate segment derived from 9,10‐dihydro‐9‐oxo‐10‐phosphaphenanthrene‐10‐oxide (DOPO) within its primary structure. In comparison to pure WPU, the limiting oxygen index (LOI) of flame‐retardant WPU (FRWPU) increased from 19.6% to 29.2%. In UL‐94 testing, the FRWPU film achieved a V‐0 rating with only 6% retarding component. Additionally, in cone calorimetry tests, Total Heat Release (THR), peak Heat Release Rate (pHRR), Total Smoke Production (TSP), Smoke Production Rate (SPR), and peak Carbon Monoxide Production Rate (pCOP) are decreased by 27.7%, 16.2%, 64.6%, 61.3%, and 77.8%, respectively. The greater degree of graphitization observed in the residual carbon substantially impeded heat exchange and the emission of smoke during combustion. Flame‐retardant intermediate segments greatly improved the FRWPUs' ability to suppress smoke and remain flame‐retardant. The creation and formulation of aqueous polyurethanes that are flame‐retardant can benefit greatly from the insights and references offered by this research. [ABSTRACT FROM AUTHOR]

The mechanism of the enantioselective (4+3) cycloaddition between furan derivatives and oxyallylcations, which are generated from the corresponding oxiranes through in situ oxidation of allenamides, has been studied using DFT methods. The research has revealed that, under acid‐catalysis by a chiral non‐racemic phosphoramide, the epoxide ring‐opening proceeds without any energy barrier, while the rate‐limiting step is the electrophilic attack of the intermediate enaminium ion on the furan ring. The reaction exhibits low energy barriers when dealing with furan derivatives unsubstituted at C2 and C5. Calculations predict the formation of an achiral regioisomer for 2‐substituted furans, a prediction that has been experimentally confirmed. Additionally, the calculations accurately predict the reaction with substituted allenamides. [ABSTRACT FROM AUTHOR]

Herein, the synthesis, structure, room temperature phosphorescence, and magnetic chiroptical properties of phosphoramides 1‐6 with donor–acceptor architecture are reported.5). The electronic interactions between donor phenothiazine (PTZ) and acceptor (C6H5)n‐P = X (n = 1, 2; X = O, S, and Se)moieties in 1–6 are modulated by varying the number of donor units. The Lewis acidity of the phosphorus center is controlled by the nature of heteroatoms and the number of phenyl moieties attached to it. All compounds exhibit phosphorescence in the solid state under ambient conditions with a photoluminescence lifetime in the millisecond range (≈8–40 ms). The energy of the phosphorescence bands and their excited state lifetimes are governed by the P=X units. The phosphorescence features observed for 1–6 are in complete contrast to the observations noted for (PTZ)3P = X (X = O, S, and Se), where the phosphorescence process is completely controlled by the PTZ moiety, and there is a negligible contribution from the P = X moiety. Thus, the present and earlier studies together reveal that the steric crowding and the number of C6H5 moieties around the P = X unit play a crucial role in controlling the electronic coupling between the donor and acceptor moieties in phosphoramides containing non‐planar donor moieties. Furthermore, for the first time, the magnetic chiroptical properties of achiral phosphoramides 1–6, exhibiting a luminescence dissymmetry factor (gMCPL) in the order of 10−3 (≈4.0 × 10−3–7.4 × 10−3) are demonstrated. [ABSTRACT FROM AUTHOR]

Phosphoramides represent an important class of organophosphorus compounds that have widespread applications in industry, agriculture, chemical synthesis as well as biomedicine. Researchers have conducted intensive and extensive studies on the properties and synthetic methods of phosphamides, including optimization and improvement of the preparative procedures and expansion of compound types. This paper presents an overview of the classical and recently reported methods for efficient construction of P-N bonds. [ABSTRACT FROM AUTHOR]

In this study, two novel phosphoramides containing 2-Amino-1,4-naphthaquinone, O,O -diethyl (2-naphthaleneyl-1,4-dione)phosphoramidothioate (NPT) and N,N´- bis(2-naphthaleneyl-1,4-dione) phenylphosphonic diamide (NPA) as cytotoxic agents, were synthesized and characterized by using spectroscopic methods. The anticancer activities of the synthesized compounds were investigated against the human breast cancer cell line SK-BR-3 and normal cells PC12 using MTT assay. The resulting data showed that NPA with an IC 50 value of 6.384 μg/ml had a better inhibitory effect against cancer cells than NPT (IC 50 = 10.08 μg/ml). According to the annexin V‐FITC/PI results, after treating cancer cells with synthesized compounds for 24 h, the overall population of apoptotic cells increased from 14.96% in the control group to 97.45%, 75.58% in NPA and NPT -treated cells, respectively. Given these results, NPA and NPT have considerable toxicity and apoptosis-inducing ability against SK-BR-3. The cytotoxicity results were supported by a molecular docking study to compute the interactions between synthesized compounds and transcription factor DNA (PDB ID: 1bg1). In order to know the structure-activity relationship (SAR) of synthesized compounds, the values of the quantum-mechanical descriptors were investigated computationally by the DFT method, and the obtained results were then compared with Cyclophosphamide (CY) as a standard anticancer drug. These results were in good accordance with those of in vitro investigation and molecular docking study. Antibacterial study of phosphoramides against Gram-negative (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) was carried out MIC, MBC and DDA methods. Additionally, the molecular docking study was performed for the interaction between E. coli beta-lactamase (PDB: 4HBT) and S. aureus beta-lactamase (PDB: 1MWU) with target compounds, the obtained results showed that these compounds are appropriate ligands for antibacterial activity against Staphylococcus aureus and Escherichia coli bacteria. [Display omitted] • Two novel phosphoramides containing 2-amino-1,4-naphthaquinone were synthesized and characterized. • Cytotoxicity studies revealed a notable dose- dependent against human breast cancer cells. • Synthesized compounds had a significant apoptosis-inducing ability at different concentrations. • DFT calculations and molecular docking simulation were applied to support the cytotoxicity results. • The obtained results showed that these compounds are appropriate for antibacterial activity. [ABSTRACT FROM AUTHOR]

A corrigendum was issued for the research article "Mechanistic Insights on the Enantioselective (4+3) cycloaddition between Oxyallylcations and Furans Catalyzed by BINOL‐based Phosphoramides" by Manuel Pedrón et al. The correction pertains to an error in the transcription of data shown in Figure 9, specifically related to transition structures of the chiral model explaining enantioselection. The authors confirm that the conclusions of the paper remain unchanged despite this error. [Extracted from the article]

In recent years, research on organophosphorus compounds, particularly phosphoramidates PRA and phosphonamides PNA, has attracted the attention of scientists because of the manifold applications of PCR and PNA. They are formally derived from phosphoramidic acids O = P(OH)(NR2)2, O = P(OH)2(NR2) and phosphonamidic acids R-PO(OH)(NR2)2 by substitution of OH for NR2. Numerous reviews dedicated to phosphoramides and phosphonamides have been published. The purpose of this current review is to present different synthetic methodologies for the synthesis of phosphoramidates and phosphonamides by use of conventional approaches or alternative strategies under green chemistry conditions. Besides the syntheses, the corresponding reaction mechanisms and applications of these compounds are discussed. [ABSTRACT FROM AUTHOR]

Two phosphoramide extractants, namely, hexapropyl phosphoramide (HPPA) and hexabutyl phosphoramide (HBPA), were developed in our laboratory for their application toward actinide separations. Preliminary studies on actinides with phosphoramides revealed that they are potential extractants for actinide recovery. However, the knowledge of extraction and stripping of U(VI), Th(IV), and Pu(IV) is essential for deploying it to plant-level reprocessing applications. In this context, the extraction behavior of U(VI) by 1.1 M solution of HBPA in n-dodecane and HPPA in xylene was studied. To gain insights into the U(VI) extraction behavior with phosphoramides, we have applied density functional theory (DFT) calculations on ligands and the corresponding metal complexes. Our estimates indicate that the ν(P = O) is red-shifted upon complex formation, which implies a moderate weakening of the P = O bond. A considerable amount of charge is transferred from the P = O group to U(VI) during complex formation. In addition to this, the computed extraction behavior was consistent with the trend established by experimental distribution ratios. These studies are useful for developing solvent extraction-based separation procedures to separate and purify actinides using a phosphoramide-based solvent. [ABSTRACT FROM AUTHOR]

Pesticides has transformed the agricultural industry, primarily by enhancing productivity. However, the indiscriminate use of such compounds can adversely affect human health and disrupt ecosystem balance. Limited knowledge exists regarding the removal of these compounds from water, particularly for organophosphate pesticides when employing conventional treatment technologies. Therefore, this study aimed to assess the removal of acephate (ACE) and methamidophos (MET) - considered priority pesticides in Brazil - from waters with high and low turbidity during the clarification process carried out with aluminum sulfate (AS) and ferric chloride (FC), either alone or combined with powdered activated carbon (PAC) adsorption. All water samples were submitted to solid phase extraction (SPE C18 cartridges) prior to acephate and methamidophos analysis by HPLC MS/MS. The clarification process with either AS or FC coagulant did not efficiently remove acephate or methamidophos and maximum average removal (27 %) was observed with waters of high turbidity when using ferric chloride as coagulant. Addition of mineral PAC was also ineffective for removing both pesticides. However, the use of vegetable PAC (10 mg/L) resulted in better removal percentages, up to 80%, but only for methamidophos. The limited removal rates were attributed to the high hydrophilicity of acephate and methamidophos, along with their neutral charge at coagulation pH. These factors hinder the interaction of such organophosphorus pesticides with the flocs formed during coagulation as well as with PAC surface., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Acephate is commonly used as a seed treatment (ST) in precision agriculture, but its impact on pollinators, earthworms, and soil microorganisms remains unclear. This study aimed to compare the fate of acephate seed dressing (SD) and seed coating (SC) treatments and assess potential risks to bees, earthworms, and soil microorganisms. Additionally, a follow-up study on maize seeds treated with acephate in a greenhouse was conducted to evaluate the maize growth process and the dissipation dynamics of the insecticide. The results indicated that acephate SC led to greater uptake and translocation in maize plants, resulting in lower residue levels in the soil. However, high concentrations of acephate metabolites in the soil had a negative impact on the body weight of earthworms, whereas acephate itself did not. The potential risk to bees from exposure to acephate ST was determined to be low, but dose-dependent effects were observed. Furthermore, acephate ST had no significant effect on soil bacterial community diversity and abundance compared to a control. This study provides valuable insights into the uptake and translocation of acephate SD and SC, and indicates that SC is safer than SD in terms of adverse effects on bees and nontarget soil organisms., Competing Interests: Declaration of competing interest No potential conflicts of interest were reported by the authors., (Copyright © 2024. Published by Elsevier B.V.)

To assess the dietary exposure risks of pesticide residues in vegetables for the general population, the presence of 39 pesticides was determined in 70 samples, of which 13 were detected. The most frequently detected pesticide was bifenthrin, with a detection rate of 35.7%, mainly found in gingers, followed by isoprocarb and acephate (11.4%) and dimethoate (8.6%). In 17.1% of the samples two or more pesticide residues were found. Acute, chronic and chronic cumulative dietary exposure risk was assessed. Chronic exposure risks were determined by Monte Carlo Simulation (MCS). Estimated chronic exposure to carbofuran, omethoate, disulfoton and dimethoate of approximately 49%, 52%, 40% and 3%, respectively, were at non-carcinogenic human risk. Acute exposure risk to acephate was considered to be of concern due to the high acute hazard quotient (aHQ).

Hexapropyl phosphoramide (HPPA) and Hexabutyl phosphoramide (HBPA), which are structural analogs of Tributyl phosphate, are the novel extractants developed for the processing of spent nuclear fuel. For the commercial use of the above extractants in reprocessing plants, data on the thermophysical properties such as density, viscosity, interfacial tension (IFT) and radiation stability are needed to develop engineering-level flow sheets for liquid-liquid extraction process. In this work, we estimated the density, viscosity and IFT of binary mixtures of HPPA and HBPA in n-dodecane pre-equilibrated with 3.5 mol.kg−1 HNO3 and also without pre-equilibration. In addition, the effect of concentration and temperature on the thermophysical properties of these solvent systems was also investigated. Both the density and viscosity of HPPA and HBPA decrease with an increase in temperature and dilution with n-dodecane. The thermal expansion coefficients of neat extractants were lower than their diluted counterpart. From the variation of viscosities with temperature, the activation energy for viscous flow was calculated and increased with extractant concentration. The IFT of HBPA and HPPA systems was higher and the zirconium retention capacities of the irradiated phosphoramides were lower than the TBP system, indicating the feasibility of HPPA and HBPA for actinide separation processes.

A series of (S)‐proline‐based enantiopure phosphorus triamide derivatives were prepared and evaluated as HMPA alternative in samarium diiodide cyclization reactions of N‐acylated indole derivatives. The expected tricyclic indoline derivatives were generally obtained in good to excellent yields, however, the induced enantioselectivities were at best moderate. In our model reaction, the phosphorus triamide derivative with a (dimethyl)hydroxymethyl group at the stereogenic center provided the cyclization product in almost quantitative yield and with an enantiomeric excess of approximately 24 %. No separate proton source is required by applying this chiral Lewis base which was recovered in 93 % yield. Bulkier substituents at the stereogenic center did not furnish improved results. Although in our preliminary study only low to moderate enantioselectivities could be achieved, the observed fast conversions and the high yields demonstrate the basic suitability of chiral pyrrolidine‐based phosphoramide Lewis bases in samarium(II)‐induced reactions. [ABSTRACT FROM AUTHOR]

Tandem, one‐pot, multicomponent reaction for direct α‐C(sp3)−H alkylation of phosphoramides and thiophosphoramides scaffolds are illustrated. The basic nature of phosphoramide leads to a diverse set of in situ generated Michael acceptors making the reactions highly atom and step economical. The reaction conditions are mild, entirely metal‐ and external additives free. Alkylated phosphoramides were obtained with good yields and selectivity using visible‐light organo‐photocatalysis. [ABSTRACT FROM AUTHOR]

Hexapropyl phosphoramide (HPPA) and hexabutyl phosphoramide (HBPA) were examined for the macrolevel extraction and stripping of tetravalent metal ions such as Pu(IV) and Th(IV). The solvation number of Pu(IV) with both the phosphoramides were measured. The number of stages was evaluated for the quantitative extraction and stripping of Pu(IV) and Th(IV) in cross-current mode with 1.1 M phosphoramides in xylene from the nitric acid medium. The distribution ratios for the extraction of Th(IV) were measured with 1.1 M phosphoramides in xylene as a function of equilibrium aqueous phase Th(IV) and nitric acid concentration. In addition, distribution ratios for the extraction of fission product elements such as Zr, Tc, Ru, lanthanides (La, Pr, Nd and Gd) and activation product Am were also measured with 1.1 M HPPA and HBPA in n-Dodecane (n-DD) system as a function of aqueous phase nitric acid concentration. The extraction data generated with phosphoramides were compared with a 1.1 M TBP/n-DD system. [ABSTRACT FROM AUTHOR]

A novel nanopattern technique of nanospherical-lens photolithography is introduced to fabricate the InGaN nanopyramid white (NPW) light-emitting diodes (LEDs) by selective area growth. Highly ordered NPW LED arrays are achieved after optimizing the growth conditions. It is found that the NPW LEDs vary from warm white light to cool with the increase in growth temperature. For the cool white NPW LEDs, the spectrum is similar to the conventional white LEDs obtained from the blue LEDs combined with yellow phosphors. The blue emission originates from the upper sidewalls of nanopyramids, and yellow light is mainly emitted from the lower ridges with respect to the base of nanopyramids. Furthermore, simulation shows that the light extraction efficiency of NPW LEDs is about 4 times higher compared with conventional ones, and the escape cone is as much as 85° due to their three-dimensional nanopyramid structures. These observations suggest that the proposed phosphor-free NPW LEDs may have great potential for highly efficient white lighting. [ABSTRACT FROM AUTHOR]

The crystal structures of two single‐enantiomer amidophosphoesters with an (O)2P(O)(N) skeleton and one single‐enantiomer phosphoric triamide with an (N)2P(O)(N) skeleton were studied. The compounds are diphenyl [(R)‐(+)‐α‐4‐dimethylbenzylamido]phosphate, (I), and diphenyl [(S)‐(−)‐α‐4‐dimethylbenzylamido]phosphate, (II), both C21H22NO3P, and N‐(2,6‐difluorobenzoyl)‐N′,N′′‐bis[(R)‐(+)‐α‐ethylbenzyl]phosphoric triamide, C25H28F2N3O2P, (III). The asymmetric units contain two amidophosphoester molecules for (I) and (II), and one phosphoric triamide molecule for (III). In the crystal structures of (I) and (II), molecules are assembled in a similar one‐dimensional chiral ribbon architecture, but with almost a mirror‐image relationship with respect to each other through N—H...O(P) and C—H...O(P) hydrogen bonds along [010]. In the crystal structure of (III), the chiral tape architecture along [100] is mediated by N—H...O(P) and N—H...O(C) hydrogen bonds, and the tapes are connected into slabs by C—H...O interactions (along the ab plane). The differences/similarities of the two diastereotopic phenoxy groups in (I)/(II) and the two chiral amine fragments in (III) were studied on the grounds of geometry, conformation and contribution to the crystal packing, as well as 1H and 13C signals in a solution NMR study. [ABSTRACT FROM AUTHOR]

Acetylcholinesterase (AChE) has emerged as a significant biological recognition element in the biosensor field, particularly for the detection of insecticides. Nevertheless, the weak thermostability of AChE restricts its utilization due to the complexities associated with production, storage, and application environments. By evaluating the binding affinity between representative AChE and insecticides, an AChE from Culex pipiens was screened out, which displayed a broad-spectrum and high sensitivity to insecticides. The C. pipiens AChE (CpA) was subsequently expressed in Escherichia coli (E. coli) as a soluble active protein. Furthermore, a three-point mutant, M4 (A340P/D390E/S581P), was obtained using a semi-rational design strategy that combined molecular dynamics (MD) simulation and computer-aided design, which exhibited a four-fold increase in half-life at 40 °C compared to the wild-type (WT) enzyme. The mutant M4 also demonstrated an optimal temperature of 50 °C and a melting temperature (T m ) of 51.2 °C. Additionally, the sensitivity of WT and M4 to acephate was examined, revealing a 50-fold decrease in the IC 50 value of M4. The mechanism underlying the improvement in thermal performance was elucidated through secondary structure analysis and MD simulations, indicating an increase in the proportion of protein helices and local structural rigidity. MD analysis of the protein-ligand complexes suggested that the enhanced sensitivity of M4 could be attributed to frequent specific contacts between the organophosphorus (OP) group of acephate and the key active site residue Ser327. These findings have expanded the possibilities for the development of more reliable and effective industrial enzyme preparations and biosensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The tarnished plant bug, (TPB) Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) is a key pest of cotton in the midsouth region and some areas of the eastern United States. Its control methods have been solely based on chemical insecticides which has contributed to insecticidal resistance and shortened residual periods for control of this insect pest. This study was conducted over a two-year period and examined the efficacy and residual effect of four commercial insecticides including lambda-cyhalothrin (pyrethroid), acephate (organophosphate), imidacloprid (neonicotinoid), and sulfoxaflor (sulfoxamine). The effectiveness and residual effects of these insecticides were determined by application on cotton field plots on four different dates during each season using three different concentrations (high: highest labeled commercial dose (CD), medium: 1/10 of the CD, low: 1/100 of the CD) on field cotton plots. Four groups of cotton leaves were randomly pulled from each treated plot and control 0-, 2-, 4-, 7-, and 9-days post treatment (DPT) and exposed to a lab colony of TPB adults. One extra leaf sample/ plot/ spray /DPT interval (0-2-4-7-9-11) during 2016 was randomly collected from the high concentration plots and sent to Mississippi State Chemical Laboratory for residual analysis. Mortality of TPB adults was greatest for those placed on leaves sprayed with the organophosphate insecticide with mortalities (%) of 81.7±23.4 and 63.3±28.8 (SE) 1-day after exposure (DAE) on leaves 0-DPT with the high concentration for 2016 and 2017, respectively, reaching 94.5±9.5 and 95.4±7.6 6-DAE each year. Mortality to all insecticides continued until 9 and 4-DPT for high and medium concentrations, respectively. However, organophosphate (39.4±28.6) and pyrethroid (24.4±9.9) exhibited higher mortality than sulfoxamine (10.6±6.6) and the neonicotinoid (4.0±1.5) 7-DAE on 9-DPT leaves with the high concentration. Based on our results using the current assay procedure, TPB adults were significantly more susceptible to contact than systemic insecticides and due to its residual effect, organophosphate could kill over 80% of the TPB population 7-DPT., Competing Interests: The authors have declared that no competing interest exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Due to rapidly developed resistance, pest management relies less on pyrethroids to control economically damaging infestations of the tarnished plant bug (TPB), Lygus lineolaris (Palisot de Beauvois) in cotton fields of Mississippi. Yet, pyrethroid resistance remains prevalent in TPB populations. This study assessed the resistance levels in adult TPB to six common pyrethroids and acephate. Resistant TBPs were collected from wild host plants in late October after harvest in the Mississippi Delta region of the United States. Based on LC 50 values, the field-resistant TPBs displayed higher resistance to permethrin, esfenvalerate, and bifenthrin (approximately 30 fold) and moderate resistance to λ-cyhalothrin, β-cyfluthrin, ζ-cypermethrin, and acephate (approximately 15 fold). Further investigations showed that the inhibitors of three detoxification enzyme, triphenyl phosphate (TPP), diethyl maleate (DEM), and piperonyl butoxide (PBO) had synergistic effects on permethrin, λ-cyhalothrin, and bifenthrin in resistant TPBs. Furthermore, elevated esterase, GST, and P450 activities were significantly expressed in field-resistant TPBs. Additionally, GST and esterase were reduced after 48 h exposure to certain pyrethroids at LC 50 dose. The synergistic and biochemical assays consistently indicated that P450 and esterase were involved in pyrethroid detoxification in TPBs. This study provides valuable information for the continued use of pyrethroids and acephate in controlling TPBs in cotton fields in the Mississippi Delta region of the United States., (Published 2023. This article is a U.S. Government work and is in the public domain in the USA.)

Bacillus genera, especially among rhizobacteria, are known for their ability to promote plant growth and their effectiveness in alleviating several stress conditions. This study aimed to utilize indigenous Bacillus cereus PM38 to degrade four organophosphate pesticides (OPs) such as chlorpyrifos (CP), profenofos (PF), monocrotophos (MCP), and dimethoate (DMT) to mitigate the adverse effects of these pesticides on cotton crop growth. Strain PM38 exhibited distinct characteristics that set it apart from other Bacillus species. These include the production of extracellular enzymes, hydrogen cyanide, exopolysaccharides, Indol-3-acetic acid (166.8 μg/mL), siderophores (47.3 μg/mL), 1-aminocyclopropane-1-carboxylate deaminase activity (32.4 μg/mL), and phosphorus solubilization (162.9 μg/mL), all observed at higher concentrations. This strain has also shown tolerance to salinity (1200 mM), drought (20% PEG-6000), and copper and cadmium (1200 mg/L). The amplification of multi-stress-responsive genes, such as acdS, ituC, czcD, nifH, sfp, and pqqE, further confirmed the plant growth regulation and abiotic stress tolerance capability in strain PM38. Following the high-performance liquid chromatography (HPLC) analysis, the results showed striking compatibility with the first kinetic model. Strain PM38 efficiently degraded CP (98.4%), PF (99.7%), MCP (100%), and DMT (95.5%) at a concentration of 300 ppm over 48 h at 35 °C under optimum pH conditions, showing high coefficients of determination (R 2 ) of 0.974, 0.967, 0.992, and 0.972, respectively. The Fourier transform infrared spectroscopy (FTIR) analysis and the presence of opd, mpd, and opdA genes in the strain PM38 further supported the potential to degrade OPs. In addition, inoculating cotton seedlings with PM38 improved root length under stressful conditions. Inoculation of strain PM38 reduces stress by minimizing proline, thiobarbituric acid-reactive compounds, and electrolyte leakage. The strain PM38 has the potential to be a good multi-stress-tolerant option for a biological pest control agent capable of improving global food security and managing contaminated sites., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A metal‐free C−P bond cleavage reaction is described herein. Phosphoramides, a phosphine source, can react with alcohols to produce phosphonate and phosphinate derivatives in the presence of a disulfide. P−H2, P‐alkyl, and P,P‐dialkyl phosphoramides can be used as substrates to obtain the corresponding pentavalent phosphine products. [ABSTRACT FROM AUTHOR]

Organophosphorus pyrrolidine derivatives possessing P–N bonds are a promising yet underexplored class of compounds. In this short review we overview the general approaches to these compounds described so far, with a special emphasis on their asymmetric synthesis. 1 Introduction 2 Synthesis of Pyrrolidine-Based P(III) Derivatives 3 Synthesis of Pyrrolidine-Based P(V) Derivatives 3.1 Phosphorylation of Pyrrolidines with P(V) Acid Chlorides 3.2 Phosphorylation of Pyrrolidines with P(V) Acid Esters 3.3 Syntheses via the Atherton–Todd Reaction 3.4 Oxidation of Pyrrolidine-Based P(III) Derivatives 4 Syntheses of N -Phosphorylpyrrolidines from Acyclic Precursors 5 Conclusions [ABSTRACT FROM AUTHOR]

Phosphoramides and thiophosphoramides were prepared from optically pure C2‐symmetric 1,2‐diamines and were used as chiral organocatalysts in the asymmetric Michael additions of aldehydes and ketones to N‐substituted maleimides. The 1,2‐diphenylethane‐1,2‐diamine derived thiophosphoramide, which could be prepared in good yield in a one‐step procedure, was found to be more active and selective catalyst in the addition of aldehydes to various maleimide derivatives, when compared to sulfonamides having the same backbone. Products resulted in reactions of ketones with maleimides were also obtained in high yields and enantioselectivities. The thiophosphoramide derivative was also efficient in the asymmetric conjugate addition of carbonyl compounds to β‐nitrostyrene and in the reaction of nitromethane with α,β‐unsaturated ketones. Based on results obtained with (thio)phosphoramides in asymmetric additions to maleimides it was suggested that a weaker, more flexible hydrogen‐bonding of the rigid electrophile to the catalyst is responsible for the improved performance of these bifunctional organocatalysts, as compared with sulfonamides. [ABSTRACT FROM AUTHOR]

Phosphoramides, as a kind of high-efficient fire retardants, have been designed in many structures and endowed exceptional fire retardancy to polylactide (PLA). However, due to ignorance of the structure-property correlation, the effect of phosphoramides' structure on the fire retardancy and mechanical properties of PLA is still unclear. Herein, a series of biobased phosphoramides (phosphoramide (V1), linear polyphosphoramide (V2) and hyperbranched polyphosphamide (V3)) were designed and incorporated into PLA, and the structural effect of phosphoramides on the fire-retardant and mechanical properties of PLA was deeply researched. Among three kinds of phosphoramides, the hyperbranched polyphosphoramide is more effective than the corresponding linear polyphosphoramide and phosphoramide in improving the fire-retardant and anti-dripping properties of PLA, and only linear polyphosphoramide shows a positive effect in the mechanical strength of PLA. This work provides a feasible strategy for creating mechanically robust and fire-retardant polymer composites by molecularly tailoring the structure of fire retardants and uncovering their structure-property relationship. [Display omitted] • The structure-property correlation of PLA/phosphoramides was unveiled. • Hyperbranched polyphosphoramide shows the best performance in fire retardancy and anti-dripping behaviors of PLA. • Linear polyphosphoramide can simultaneously improve the tensile strength, elastic modulus and fire retardancy of PLA. [ABSTRACT FROM AUTHOR]

The phosphoramide phosphorus ester phosphate ammonium (PPEPA) flame retardant was synthesized by phosphorus oxychloride and ethanolamine, and its structure was characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy (FTIR). Cotton textiles treated with 20 wt% PPEPA (CT-PPEPA3) would have high durability and flame retardance. The limiting oxygen index (LOI) of CT-PPEPA3 was found to be 46.5 %, while after undergoing 50 laundering cycles (LCs) following the AATCC 61-2013 3 A standard, the LOI only decreased to 31.4 %. Scanning electron microscopy and X-ray diffraction analyses suggested the penetration of PPEPA molecules into the interior of cotton fibers, resulting in a minor alteration of the cellulose crystal structure. The excellent durability, FTIR, and energy-dispersive X-ray of CT-PPEPA3 provided evidence for the formation of -N-P(=O)-O-C- and -O-P(=O)-O-C- covalent bonds between the PPEPA molecules and cellulose. The -N-P(=O)-O-C- bond exhibited a p-π conjugation effect, leading to enhanced stability and improved durability of the flame-retardant cotton textiles. Vertical flame, thermogravimetric, and cone calorimetry tests demonstrated that the CT-PPEPA3 underwent condensed-phase and synergistic flame retardation. Additionally, these finished cotton textiles retained adequate breaking strength and softness, making them suitable for various applications. In conclusion, the incorporation of the -N-P(=O)-ONH 4 group into the phosphorus ester phosphate ammonium flame retardant demonstrated effective enhancement of the fire resistance and durability of treated cotton textiles., Competing Interests: Declaration of competing interest No conflict of interest pears for the manuscript submission., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Twelve new zinc(II) and cadmium(II) complexes with symmetric ligands, [MCl2((R2N)3PO)2] (M = Zn, R2N = pyrrolidinyl (1), piperidinyl (2); M = Cd, R2N = pyrrolidinyl (3), piperidinyl (4)), and differently substituted ligands of the general formula [MCl2(R2N)PO(R'2N)2] (M = Zn or Cd; R2N = Pyrr, Pip or Mor; R'2N = Pyrr, Pip or Mor (5–12) have been synthesized from reaction of zinc(II) or cadmium(II) chlorides with the ligands, giving yields of 43–76%. The complexes were characterized with multinuclear (1H, 13C and 31P) NMR, conductivity, IR spectroscopy, and X-ray analyses. Complexes 1, 3, 11, and 12 are comprised of two ligands coordinated to the metal center in a distorted monomeric tetrahedral arrangement. The P = O bond lengths of 1.490(3) (1), 1.497(4) (3), 1.480(4) (11), and 1.479(5) Å (12) are in the order observed for analogous phosphoramide complexes. The results are compared with those reported for related chalcogen counterparts. [ABSTRACT FROM AUTHOR]

Crystal structures of six new phosphoramides with the main parts [C(O)NH]P(O)[N]2 and [NH]2P(O)[N] were determined by single crystal X‐ray diffraction and characterized by spectroscopic methods (FT‐IR and 1H, 13C, 31P NMR). X‐ray crystallography data manifest that the hydrogen bond interactions N−H...O (in all structures) accompanied by some contacts such as C−H...X (X=π, O, F and Cl) and π...π dominate the molecular architectures. Some non‐classical interactions such as Cl...π are also found in feature packing of some studied structures. A detailed investigation of these intermolecular interactions in order to illustrate the importance of non‐classical interactions in construction of molecular assemblies is presented by Hirshfeld surface (HS) analysis reflected the most important van der Waals (vdW) contributions and "Quantum Theory Atom In Molecule" (QTAIM) method especially in term of energetic feature. Hirshfeld surface analysis reveals that the prevalent interactions are of the type O...H for all structures coupled with some other short contacts such as C...C and H...F recognized by red spots on Hirshfeld surfaces and enrichment ratios (E) larger than unity (E > 1). These results are confirmed by AIM method classifying the hydrogen bond interactions N−H...O as moderate non‐covalent closed‐shell interactions and the remaining interactions above‐mentioned as vdW closed‐shell interactions in the studies phosphoric triamides. Such study to categorize the popular hydrogen bond interactions N−H...O in phosphoric triamides and the weak interactions in their molecular packing are used for the first time. [ABSTRACT FROM AUTHOR]

Based on Mie scattering and Monte Carlo ray tracing method, the transmission process of light in the remote phosphor film is described and the optical model of red and green laminated phosphor films is constructed. The photochromic properties of the phosphor films were studied by TM-30-15 method proposed by the North American Lighting Association. The investigation discloses that the normalized cross correlation of single-layer phosphor film spectral power distribution between the simulation and experimental results is about 99%, and the deviation of color coordinates is within 0.01. Based on the monochrome phosphor optical model, we establish bicolor optical model of red and green laminated phosphor film layers to form white light and can predict its color performance. The experimental results show that the normalized cross correlation of laminated phosphor film spectral power distribution between the simulation and experiment is about 97%, and the optical model of red and green laminated phosphor film can accurately predict the index Rf and Rg. When the red and green phosphor mass ratio is 0.05:0.5, the simulated color is optimal, Rf reaches 90, and Rg reaches 100, whose corresponding experimental values are Rf=90, Rg=101. [ABSTRACT FROM AUTHOR]

In this work, we for the first time conducted a detailed study on the structure, dynamics, and hybridization properties of N-benzimidazole group-bearing phosphoramide benzoazole oligonucleotides (PABAOs) that we developed recently. By circular dichroism we established that the introduction of the modifications does not disrupt the B conformation of the DNA double helix. The formation of complexes is approximated by a two-state model. Complexes of PABAOs with native oligodeoxriboynucleotides form efficiently, and the introduction of such modifications reduces thermal stability of short duplexes (8-10 bp) by ∼5°С per modification. Using UV-spectroscopy analysis, a neutral charge of the phosphate residue modified by the N-benzimidazole moiety in the pH range of 3-9.5 was found. The results confirm possible usefulness of PABAOs for both basic research and biomedical applications., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Alexander A. Lomzov reports financial support was provided by Russian Science Foundation. Alexader Lomzov has patent Phosphoramide azole oligonucleotides, a method for the synthesis of phosphoramide azole oligonucleotides and a method for template enzymatic DNA synthesis using them pending to 2023110694. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Detection of the Kirsten rat sarcoma gene ( KRAS ) mutational status is an important factor for the treatment of various malignancies. The most common KRAS -activating mutations are caused by single-nucleotide mutations, which are usually determined by using PCR, using allele-specific DNA primers. Oligonucleotide primers with uncharged or partially charged internucleotide phosphate modification have proved their ability to increase the sensitivity and specificity of various single nucleotide mutation detection. To enhance the specificity of single nucleotide mutation detection, the novel oligonucleotides with four types of uncharged and partially charged internucleotide phosphates modification, phosphoramide benzoazole (PABA) oligonucleotides (PABAO), was used to prove the concept on the KRAS mutation model. The molecular effects of different types of site-specific PABA modification in a primer or a template on a synthesis of full-length elongation product and PCR efficiency were evaluated. The allele-specific PCR (AS-PCR) on plasmid templates showed a significant increase in analysis specificity without changes in Cq values compared with unmodified primer. PABA modification is a universal mismatch-like disturbance, which can be used for single nucleotide polymorphism discrimination for various applications. The molecular insights of the PABA site-specific modification in a primer and a template affect PCR, structural features of four types of PABAO in connection with AS-PCR results, and improvements of AS-PCR specificity support the further design of novel PCR platforms for various biological targets testing.

Introduction: Chronic hepatitis C virus (HCV) persists as a public health concern worldwide. Consequently, optimizing HCV therapy remains an important objective. While current therapies are generally highly effective, advanced antiviral agents are needed to maximize cure rates with potentially shorter treatment durations in a broader patient population, particularly those patients with advanced diseases who remain difficult to treat., Areas Covered: This review summarizes the in vitro anti-HCV activity, preclinical pharmacological properties of bemnifosbuvir (BEM, AT-527), a novel prodrug that is metabolically converted to AT-9010, the active guanosine triphosphate analogue that potently and selectively inhibits several viral RNA polymerases, including the HCV NS5B polymerase. Results from clinical proof-of-concept and phase 2 combination studies are also discussed., Expert Opinion: BEM exhibits potent pan-genotype activity against HCV, and has favorable safety, and drug interaction profiles. BEM is approximately 10-fold more potent than sofosbuvir against HCV genotypes (GT) tested in vitro. When combined with a potent NS5A inhibitor, BEM is expected to be a promising once-daily oral antiviral for chronic HCV infection of all genotypes and fibrosis stages with potentially short treatment durations.

Reductive electrosynthesis has faced long-standing challenges in applications to complex organic substrates at scale. Here, we show how decades of research in lithium-ion battery materials, electrolytes, and additives can serve as an inspiration for achieving practically scalable reductive electrosynthetic conditions for the Birch reduction. Specifically, we demonstrate that using a sacrificial anode material (magnesium or aluminum), combined with a cheap, nontoxic, and water-soluble proton source (dimethylurea), and an overcharge protectant inspired by battery technology [tris(pyrrolidino)phosphoramide] can allow for multigram-scale synthesis of pharmaceutically relevant building blocks. We show how these conditions have a very high level of functional-group tolerance relative to classical electrochemical and chemical dissolving-metal reductions. Finally, we demonstrate that the same electrochemical conditions can be applied to other dissolving metal–type reductive transformations, including McMurry couplings, reductive ketone deoxygenations, and epoxide openings. [ABSTRACT FROM AUTHOR]

Phosphoramides are an interesting alternative to the thiourea motif that has long been used in organocatalysis. In the R1N(H)‐P(O)(R3)‐N(H)R2 formulation, phosphoramides give the advantage of having a third variable substituent, R3, compared to the two available in thioureas, and the possibility of introducing chirality with an asymmetric phosphorus center. In this work, we present a systematic computational study on the catalytic properties of these underexplored compounds. These studies show the catalytic potential of a series of substituted phosphoramides in Diels–Alder reactions, including the asymmetric [4+2] cycloaddition of pro‐chiral substrates. The nature of the phosphorus‐bound R3 substituent has a significant impact both on catalytic activity and enantioselectivity. Remarkably, several of the phosphoramides studied are predicted to be more active than the Schreiner's thiourea organocatalyst. Phosphoramides are explored as an alternative to the thiourea motif in the catalytic Diels–Alder reaction. Computational studies show the high potential of these compounds, with predicted catalytic activities higher than that of Schreiner's thiourea organocatalyst and the possibility of introducing enantioselectivity with a chiral phosphorus center. [ABSTRACT FROM AUTHOR]

An electrochemical method to achieve carbamoylphosphonates from phosphoramides and alcohols via P–H oxidation and functionalization by using n-Bu4NI as a catalyst is reported. A series of carbamoylphosphonates were obtained with good to excellent yields under mild reaction conditions. The electrochemical reaction is carried out under constant current electrolysis, with the alcohol being used as a solvent and a substrate, and is an attractive green synthesis method. [ABSTRACT FROM AUTHOR]

Abstract Cyclophosphamide is a prodrug that is converted to inactive carboxy-cyclophosphamide, acrolein and phosphoramide mustard, an agent that adds alkyl groups to oxygen and nitrogen atoms of guanine, one of the four nitrogen bases that form the DNA nucleotides, causing DNA cross-links and introducing DNA breaks. These cytotoxic and mutagenic effects mainly occur in proliferating cells. Repair mechanisms may prevent DNA damage in quiescent cells, but they may be insufficient to contrast the side effects of cyclophosphamide if high doses of the drug are used. Most adverse events are dose- and age-dependent. Phosphoramide mustard can cause bone marrow toxicity, gonadal toxicity, and may favor the development of leukemia, bladder cancer and other types of malignancy. Acrolein can produce hemorrhagic cystitis and even bladder fibrosis when given for prolonged periods. A number of precautional measures should be taken to prevent these untoward events. In particular, long-term administration and high doses of cyclophosphamide should be avoided whenever possible. Today the indications to cyclophosphamide in glomerular diseases are more restricted than in the past, but the drug is still used as a steroid-sparing agent in steroid-sensitive minimal change disease and focal segmental glomerulosclerosis. In membranous nephropathy, cyclophosphamide, alternated or associated with corticosteroids, proved to be beneficial in obtaining remission of nephrotic syndrome and preserving renal function. Cyclophosphamide is considered as a first-line treatment for rapidly progressive glomerulonephritis and the hectic phases of lupus nephritis. In conclusion, cyclophosphamide is a cheap drug that may be useful in a number of glomerular diseases but it may lead to severe side effects. A close monitoring of blood count and clinical conditions, as well as low cumulative doses of cyclophosphamide are strongly recommended when using the drug in patients with renal diseases. [ABSTRACT FROM AUTHOR]

The synthesis of several novel organocatalysts derived from (R)- and (S)-proline-glycine dipeptides and incorporating a chiral phosphoramide fragment was accomplished. These chiral compounds catalyze the enantioselective aldol addition reaction of cyclohexanone to prochiral aryl aldehydes and isatins in the presence of water. These chiral organocatalysts represent some of the few proline-derived compounds capable to catalyze aldol-type addition of cyclohexanone to isatins, a C-C bond forming transformation for which chiral primary amines are usually more successful. Additionally, these phosphoramide- containing catalysts afforded excellent results in the addition of cyclohexanone to aryl aldehydes, as anticipated by the presence of the proline moiety. The present report includes a detailed evaluation of the new multifunctional catalysts that are able to afford either enantiomer of the chiral product by adequate selection of the configuration of the proline residue. [ABSTRACT FROM AUTHOR]

ABSTRACT: A novel flame retardant named diethylene N,N',N''‐tri (diethoxy)phosphoramide (DTP) was synthesized using diethyl phosphate and diethylenetriamine via Atherton–Todd reaction. Then, series of flame‐retardant water‐blown rigid polyurethane foams (RPUFs) with expandable graphite (EG) and DTP were prepared through box‐foaming. The results of thermogravimetric analysis showed that DTP/EG changed thermal degradation process of RPUF and promoted enhancing char residues. The complex flame‐retardant system (EG/DTP) endowed RPUF higher limiting oxygen index (LOI) values (29.1%–30.2%) and lower heat release rate peak (PHRR) values according to LOI and microscale combustion calorimeter tests. More importantly, the synergistic flame‐retardant effect between EG and DTP in RPUF was proved by the analysis of synergistic effectivity values. Based on the analysis of cone calorimetric tests, EG/DTP revealed remarkable effects to inhibit the fire intensity and smoke release of RPUF with decreased PHRR and total smoke production due to good char‐forming action. To further investigate the char‐residues of the foams after combustion, scanning electron microscope and energy dispersive X‐ray spectroscopy analyses were conducted. The results suggested that EG/DTP flame‐retardant system promoted RPUF forming a compact, continuous and phosphorus‐rich char layer as a good fire barrier in combustion. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46434. [ABSTRACT FROM AUTHOR]

Control of absolute stereochemistry in radical and ion radical transformations is a major challenge in synthetic chemistry. Herein, we report the design of a photoredox catalyst system comprised of an oxidizing pyrilium salt bearing a chiral N- triflyl phosphoramide anion. This class of chiral organic photoredox catalysts is able to catalyze the formation of cation radical-mediated Diels-Alder transformations in up to 75:25 e.r. in both intramolecular and intermolecular examples. [ABSTRACT FROM AUTHOR]

Tetrahedral manganese(II) complexes having formulae [MnX 2 {O = PR(NMe 2 ) 2 } 2 ] (X = Br, I; R = NMe 2 , Ph) were isolated and characterized, and in the case of [MnBr 2 {O = PPh(NMe 2 ) 2 } 2 ] the structure was ascertained by means of single crystal X-ray diffraction. All the complexes showed intense green emission assigned to the Mn(II) 4 T 1 ( 4 G) →  6 A 1 ( 6 S) transition upon excitation with UV light, with photoluminescence lifetimes in the range 100–1000 μs. Bromo-complexes maintain their luminescence features once dispersed in polycaprolactone matrix. [ABSTRACT FROM AUTHOR]

Novel organocatalysts derived from (R)- and (S)-proline and incorporating a chiral phosphoramide fragment were rationally designed and subsequently synthesized. These chiral compounds catalyze the enantioselective aldol addition reaction of cyclohexanone to prochiral isatins in the presence of water. These observations are particularly relevant since reports of asymmetric aldol reactions between cyclohexanone and isatins catalyzed by chiral secondary amines remain scarce, with primary amines being the most studied and successful catalysts. The present report includes a thorough evaluation of the new bifunctional catalysts that actually give rise to either enantiomer of the chiral product by proper selection of the configuration of the proline moiety. [ABSTRACT FROM AUTHOR]