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Fosmidomycin (FOS) is a naturally occurring compound active against the 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) enzyme in the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway, and using it as a template for lead structure design is an effective strategy to develop new active compounds. In this work, by replacing the hydroxamate unit of FOS with pyrazole, isoxazole and the related heterocycles that also have metal ion binding affinity, while retaining the monophosphonic acid in FOS or replacing it with a bisphosphonic acid group, heterocycle-containing mono- and bisphosphonic acid compounds as FOS analogs were designed. The key steps involved in the facile synthesis of these FOS analogs included the Michael addition of diethyl vinylphosphonate or tetraethyl vinylidenebisphosphonate to β-dicarbonyl compounds and the subsequent cyclic condensation with hydrazine or hydroxylamine. Two additional isoxazolinone-bearing FOS analogs were synthesized via the Michaelis–Becker reaction with diethyl phosphite as a key step. The bioactivity evaluation on model plants demonstrated that several compounds have better herbicidal activities compared to FOS, with the most active compound showing a 3.7-fold inhibitory activity on Arabidopsis thaliana, while on the roots and stalks of Brassica napus L. and Echinochloa crus-galli in a pre-emergence inhibitory activity test, the activities of this compound were found to be 3.2- and 14.3-fold and 5.4- and 9.4-fold, respectively, and in a post-emergency activity test on Amaranthus retroflexus and Echinochloa crus-galli, 2.2- and 2.0-fold inhibition activities were displayed. Despite the significant herbicidal activity, this compound exhibited a DXR inhibitory activity lower than that of FOS but comparable to that of other non-hydroxamate DXR inhibitors, and the dimethylallyl pyrophosphate rescue assay gave no statistical significance, suggesting that a different target might be involved in the inhibiting process. This work demonstrates that using bioisosteric replacement can be considered as a valuable strategy to discover new FOS analogs that may have high herbicidal activities. [ABSTRACT FROM AUTHOR]

In the fabrication of inverted perovskite solar cells (PSCs), the wettability, adsorbability, and compactness of self-assembled monolayers (SAMs) on conductive substrates have critical impacts on the quality of the perovskite films and the defects at the buried perovskite-substrate interface, which control the efficiency and stability of the devices. Herein, three bisphosphonate-anchored indolocarbazole (IDCz)-derived SAMs, IDCz-1, IDCz-2, and IDCz-3, are designed and synthesized by modulating the position of the two nitrogen atoms of the IDCz unit to improve the molecular dipole moments and strengthen the π-π interactions. Regulating the work functions (WF) of FTO electrodes through molecular dipole moments and energy levels, the perovskite band bends upwards with a small offset for ITO/IDCz-3/perovskite, thereby promoting hole extraction and blocking electrons. As a result, the inverted PSC employing IDCz-3 as hole-collecting layer exhibits a champion PCE of 25.15%, which is a record efficiency for the multipodal SAMs-based PSCs. Moreover, the unencapsulated device with IDCz-3 can be stored for at least 1800 h with little degradation in performance., (© 2024 Wiley‐VCH GmbH.)

This study evaluated the ability of bisphosphonates (BPAs) of different molecular structures to mitigate the calcification of porcine aortic wall (PAW) and bovine jugular vein wall (BJVW). Tissues cross‐linked with glutaraldehyde (GA) or diepoxide (DE) were modified with pamidronic acid (PAM), alendronic acid (ALE), neridronic acid (NER) (type 1 BPAs); 2‐(2′‐carboxyethylamino)ethylidene‐1,1‐bisphosphonic acid (CEABA), 2‐(5‐carboxypentylamino)ethylidene‐1,1‐bisphosphonic acid (CPABA) (type 2); and zoledronic acid (ZOL) (type 3). After implanting the tissue samples subcutaneously in 100 rats, calcification was examined using atomic absorption spectrophotometry (60‐day explants) and light microscopy after von Kossa staining (10‐ and 30‐day explants). The calcium contents in GA‐BJVW and GA‐ and DE‐PAW increased up to 100–120 mg/g after 60 days, while being 3 times lower in DE‐BJVW. In modified and nonmodified PAW samples, calcium phosphates appeared by day 10 and were associated with elastic fibers and devitalized cellular elements. In all groups of BJVW samples, mineralization began in elastic fibers near the subendothelial layer. In addition, calcified collagen was found in the GA‐BJVW samples. Minimal calcification was found in GA‐PAW treated with type 1 BPAs and CEABA. For DE‐PAW and GA‐BJVW, the calcium level significantly decreased with PAM and CEABA. Meanwhile, ALE and NER were effective for DE‐BJVW. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carboxylated trithiocarbonate mediates RAFT polymerization of a bisphosphonic acrylate. • Two RAFT methodologies lead to phosphonated double hydrophilic block copolymers. • DHBCs interact with lanthanide ions (Gd, Eu) to form polyionic complexes. • Bisphosphonated polyionic complexes enhance the stability of MRI contrast agents. The synthesis of double hydrophilic block copolymers (DHBCs) with one block containing bisphosphonic acid groups was performed by aqueous RAFT polymerization with two approaches, either starting from a PEO-based macro-chain transfer agent (macro-CTA) or by chain extension of a RAFT-capped bisphosphonic acrylate homopolymer with oligo(ethylene glycol) methyl ether acrylate (OEGA). By complexation with gadolinium and europium ions, these polymers are prone to form hybrid polyionic complexes (HPICs) as evidenced by mono- and multi-angle DLS, TEM and luminescence measurements. The obtained HPICs showed better chemical stability at low pH values compared to previously reported counterparts based on carboxylic and monophosphonic acid groups (i.e., PEO- b -PAA and PEO- b -PVPA respectively). Due to their high relaxivity values, the proposed HPICs show potential as contrast agents for magnetic resonance imaging (MRI). [ABSTRACT FROM AUTHOR]

A bisphosphonic acid type extraction reagent has been synthesised and employed to investigate the extraction behaviour towards rare-earth metals. The new reagent exhibited extremely high extraction ability for these ions. This ability was also accompanied by low leakage of extractant into the aqueous phase reflecting the reagent's hydrophobic nature and the presence of partially undissociated phosphonic acid groups. [ABSTRACT FROM AUTHOR]

Herein we describe our recent advances in the synthesis of new bisphosphonates, containing adenosines, adenine moiety as well as reactive aminoacetal fragment and calix[4]resorcinols framework. For the synthesis of these compounds we used three main approaches: Michael addition of nucleophilic amines (adenosines, adenines and aminoacetaldehyde) to (tetraethyl)ethenylidene-1,1-bisphosphonate and tetrakis(trimethylsilyl)ethenylidene-1,1-bisphosphonate); acid catalyzed condensation of bisphosphonic acid derivatives, containing acetal group with polyphenols; formation of onium salts of bisphosphonic acids with adenosine and aminomethylated calix[4]resorcinols. [ABSTRACT FROM AUTHOR]

The first monomers containing both phosphonate and bisphosphonate (M1) or phosphonic and bisphosphonic acid (M2) functionalities are synthesized, aiming to improve binding abilities of self‐etching adhesive systems and composites: An amine having both phosphonate and bisphosphonate functionalities is prepared via Michael addition reaction between diethyl (6‐aminohexyl)phosphonate and tetraethyl vinylidene bisphosphonate, its reaction with 2‐isocyanatoethyl methacrylate gives M1 which is converted to M2 by selective dealkylation of the phosphonate/bisphosphonate ester groups. Their copolymerization with commercial dental monomers (bisphenol A glycidyl methacrylate, triethylene glycol dimethacrylate, and 2‐hydroxyethyl methacrylate) investigated by photo‐differential scanning calorimetry shows adequate photopolymerization rate and conversion. X‐ray diffraction, Fourier transform infrared, and X‐ray photoelectron spectroscopy analyses of M2‐treated hydroxyapatite particles show formation of stable M2‐calcium salts. These monomers are assessed to be not toxic according to MTT standards by in vitro cytotoxicity studies with NIH 3T3, U2OS, and Saos‐2 cells. All these properties make these monomers potential candidates as biocompatible components for dental adhesives and composites. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2739–2751 To improve efficiencies of dental materials, novel monomers containing both phosphonate and bisphosphonate/phosphonic and bisphosphonic acid are synthesized. Interaction of monomers with hydroxyapatite (mineral structure of teeth) is analyzed; their copolymerization rate and yield with the dental monomers are evaluated by using photo‐differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Currently, significant attention is attracted to the problem of the development of the specific architecture and composition of the surface layer in order to control the biocompatibility of implants made of titanium and its alloys. The titanium surface properties can be tuned both by creating an inorganic sublayer with the desired morphology and by organic top coating contributing to bioactivity. In this work, we developed a composite biologically active coatings based on hybrid molecules obtained by chemical cross-linking of amino acid bisphosphonates with a linear tripeptide RGD, in combination with inorganic porous sublayer created on titanium by plasma electrolytic oxidation (PEO). After the addition of organic molecules, the PEO coated surface gets nobler, but corrosion currents increase. In vitro studies on proliferation and viability of fibroblasts, mesenchymal stem cells and osteoblast-like cells showed the significant dependence of the molecule bioactivity on the structure of bisphosphonate anchor and the linker. Several RGD-modified bisphosphonates of β-alanine, γ-aminobutyric and ε-aminocaproic acids with BMPS or SMCC linkers can be recommended as promising candidates for further in vivo research.

Bisphosphonates had been found to act as strong metal ion complexing agents with usefulindustrial and household applications. [...]

A series of aromatic and aliphatic bis[aminomethylidene(bisphosphonic)] acids was synthesized in the reaction of triethylphosphite with isonitriles followed by hydrolysis or dealkylation. The in vitro anti-proliferative effect of all synthesized tetraphosphonic acids against MCF-7 breast cancer cells, J774E macrophages and HL-60 promyelocytic leukemia cells was determined. Three aromatic derivatives ( 5a , 5f and 5j ) showed a similar or higher anti-proliferative activity than zoledronic acid. [ABSTRACT FROM AUTHOR]

[Display omitted] • DBDP surfactant is synthesized and used as a flotation collector. • DBDP exhibits a certain specificity for magnesite. • New reverse flotation process for decalcification of magnesite is rational. • DBDP is chemisorbed on magnesite and dolomite surfaces. • DBDP provides more coordination atoms to magnesite. Magnesite and dolomite are magnesium-containing minerals with similar crystal structures, making their separation a challenge in production. In this study, the surfactant Dodecane-1,2-diyl bis (dihydrogen phosphate) (DBDP) was discovered to selectively adsorb on dolomite surface and collect dolomite from magnesite. In the single mineral flotation tests, the collector DBDP achieved a recovery difference of more than 45% under neutral condition. In the mixed minerals reverse flotation tests with sodium alginate as an inhibitor, an excellent separation result of increasing MgO grade from 44.30% to 46.13% with a magnesite recovery of 88.19% in the concentrate was obtained. Adsorption mechanism analysis confirmed that DBDP was chemically adsorbed to the Ca and Mg sites on mineral surfaces and was stronger on the surface of dolomite. The DFT calculation further established the O atoms at top of the posphonic acid group acted on the mineral surface by chemisorption, while the O atoms in C - O - P sometimes assisted by electrostatic interaction. Meanwhile, DBDP provided more active O sites on the dolomite surface, resulting in more stable adsorption than magnesite. As a result, DBDP promised an excellent performance in the novel process of removing dolomite from magnesite by reverse flotation. [ABSTRACT FROM AUTHOR]

Iron(III) in phosphate ore leach liquor harms the quality of phosphoric acid and phosphogypsum crystallization. In this paper, the selective separation of iron(III) was studied with two novel extractants, N, N-n-octylamine di(methylene phenylphosphonic acid) (OADMPPA) and N, N-n-hexadetamine di(methylene phenylphosphonic acid) (HADMPPA), from a mixed media of sulfuric acid and phosphoric acid. The effects of temperature, time, diluents, and the concentrations of sulfuric acid and extractant on the separation of iron were investigated. The mechanism of extraction was established by UV–Vis spectroscopy, FT-IR spectroscopy, slope analysis, and the equimolar series method. The results showed that the two new reagents have good extraction ability toward iron(III) even at higher sulfuric acid concentration. Both OADMPPA and HADMPPA can remove more than 99% of iron(III) from the sulfuric acid leach liquor of phosphate ore. The stripping of iron(III) from the organic phase after extraction with acidic phosphine (phosphorus) extractants was difficult. Oxalic acid was found to be a good stripping agent. The single stage stripping efficiency reached 62.8%, and the two-stage stripping efficiency could reach over 99%. The separation and recovery of iron(III) in phosphate ore leach liquor could be realized by our method without changing the traditional phosphoric acid production process, which is beneficial to the purification of phosphoric acid and the recovery of iron. • Two new extractants OADMPPA and HADMPPA were designed and synthesized. • They have high extraction rate and selectivity for Fe3+ in sulfuric acid medium. • Their extraction rates of Fe3+ were 40 times higher than common extractants. • The extraction mechanisms of Fe3+ with extractants were proved to be ion exchange. • Difficulty in stripping of Fe3+ from the loaded organic phase was resolved. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of isonitriles with trialkyl phosphites in the presence of hydrogen chloride gives tetraalkyl N-substituted aminomethylidenebisphosphonates via N-methylideneaminium (isonitrilium) salts. Hydrolysis or dealkylation of these tetraalkyl esters gives N-substituted aminomethylidenebisphosphonic acids in high yields. [Copyright &y& Elsevier]

The reaction of o-phthaloyl chloride with sodium diethylphosphite led to the formation of new 3,3-bis(diethylphosphono)-1-(3H)-isobenzofurane 1. The reaction of bis-phosphonate with alkylamine occurs with replacement of an ester oxygen by an imine group to afford the crystalline isoindolyl-bis-phosphonate-a representative of this new type of organophosphorus heterocycles. [ABSTRACT FROM AUTHOR]

Currently, significant attention is attracted to the problem of the development of the specific architecture and composition of the surface layer in order to control the biocompatibility of implants made of titanium and its alloys. The titanium surface properties can be tuned both by creating an inorganic sublayer with the desired morphology and by organic top coating contributing to bioactivity. In this work, we developed a composite biologically active coatings based on hybrid molecules obtained by chemical cross-linking of amino acid bisphosphonates with a linear tripeptide RGD, in combination with inorganic porous sublayer created on titanium by plasma electrolytic oxidation (PEO). After the addition of organic molecules, the PEO coated surface gets nobler, but corrosion currents increase. In vitro studies on proliferation and viability of fibroblasts, mesenchymal stem cells and osteoblast-like cells showed the significant dependence of the molecule bioactivity on the structure of bisphosphonate anchor and the linker. Several RGD-modified bisphosphonates of β-alanine, γ-aminobutyric and ε-aminocaproic acids with BMPS or SMCC linkers can be recommended as promising candidates for further in vivo research. [ABSTRACT FROM AUTHOR]

The present study investigated the phytoextraction ability of Salix schwerinii E.L. Wolf enhanced with an application of the chelate N10O. Salix schwerinii were grown in garden soil that was also amended with Cu (400 mg kg−1), Ni (30 mg kg−1) and Zn (200 mg kg−1). Multiple doses of N10O were applied to the treatments as follows: Cu (3.45 g and 6.9 g), Ni (1.2 g and 2.4 g), and Zn (1.45 g and 2.9 g). Furthermore, N10O doses were also repeated with the control soil. The effect of N10O on height growth, biomass production, ecophysiological attributes, and the accumulation of metals (Cu, Ni, and Zn) in Salix in polluted soils was studied. Compared to the control, the total metal concentrations in S. schwerinii growing in the soils amended with N10O increased substantially by up to 895% for Cu, 324% for Ni and 722% for Zn. The translocation factor (TF) and bioconcentration factor (BF) values for S. schwerinii increased with the application of N10O and varied from 0.30–1.01 for Cu, 0.45–1.25 for Ni, and 4.40–5.89 for Zn, whereas, BF values varied from 0.60–1.15 for Cu, 0.80–1.50 for Ni, and 4–8 for Zn. This study indicated that S. schwerinii can be used for phytoextraction of Cu, Ni and Zn from contaminated soils. However, further research is needed to examine the phytoextraction potential of other Salix species using N10O to remediate soils polluted with various toxic metals. • The use of N10O chelate is an entirely novel approach. • N10O showed a significant effect on growth and on the physiological response of plants. • N10O significantly affected uptake of metals by Salix schwerinii. • Cost efficient and effective approach for phytoextraction [ABSTRACT FROM AUTHOR]

The first bisphosphonic acid‐functionalized benzophenone (BP) and thioxanthone (TX) photoinitiators (PIs), BPBP and TXBP, are synthesized as a new class of water‐soluble PIs for free radical polymerization. BPBP shows excellent solubility (28 g L−1) in water at ambient temperature, compared to TXBP (0.05 g L−1) and also the commercial PI Irgacure 2959 (5 g L−1). BPBP and TXBP show UV–vis absorption at ≈260 (ε = 12912) and 405 (ε = 3314) nm in water. Photopolymerization results demonstrate that they can successfully initiate the photopolymerization of poly(ethylene glycol) diacrylate (Mn = 250 D) in the presence of bis‐(4‐tert‐butylphenyl)‐iodonium hexafluorophosphate (Iod). The photochemical mechanisms are investigated by electron‐spin resonance‐spin trapping, fluorescence, and steady‐state photolysis techniques. [ABSTRACT FROM AUTHOR]