Epoxysuccinic Acid Research Articles

Synthesis and evaluation of a new scale inhibitor: the modified epoxysuccinic acid copolymer

Polyepoxysuccinic acid (PESA) scale inhibitor is widely recognized as a green and environmentally friendly scale inhibitor. However, its functional group type is single and cannot be used for a variety of scales. Based on this, a modified epoxy succinic acid quaternary polymer scale inhibitor PEAPS was prepared by introducing a variety of functional groups. The effects of scale inhibitor dosage, temperature, and solution pH on the scale inhibition performance of CaCO3, CaSO4, BaSO4, and SrSO4 were studied. At the same time, it is compared with the commonly used oilfield scale inhibitors Polyacrylic acid (PAA), PESA, and Ethylenediaminetetramethylenephosphonic acid (EDTMP). The results show that under the optimal synthesis conditions, the scale inhibition efficiency of PEAPS scale inhibitor on CaCO3 scale and CaSO4 reaches 100%, and the scale inhibition efficiency of BaSO4 and SrSO4 can reach at least 60%. Its comprehensive scale inhibition efficiency is better than other commonly used scale inhibitors under the same test conditions, and it has certain corrosion inhibition performance through static corrosion evaluation. The crystal parameters and micro-morphology of the four scales before and after the addition of scale inhibitor were analyzed using SEM and XRD. The results showed that after adding the PEAPS scale inhibitor, the crystal structure parameters of the CaCO3 scale and CaSO4 scale changed, and the micro-morphology of the four scale crystals also changed, to achieve the purpose of scale inhibition.

Effect of hydrophobic chain length on the properties of polycarboxylate polymeric surfactants

In this work, a series of polycarboxylate polymeric surfactants were designed and synthesized from acrylate monomers with different alkyl chain lengths (alkyl chain lengths of 1, 4, 6, 12, 18), epoxy succinic acid (ESA), acrylic acid (AA) and 2-acrylamide-2-methylpropane sulfonic acid (AMPS). Their structures were confirmed by FT-IR, 1H NMR and GPC. A series of surfactant parameters, including critical micelle concentration (CMC), minimum surface tension, surface tension reduction at critical micelle concentration (Πcmc), surface tension reduction efficiency (pC20), etc, were obtained by surface activity test. The results showed that with the increase of the alkyl chain length of acrylate, surface tension and CMC of polycarboxylate polymeric surfactants gradually decreased. When the alkyl chain length of acrylate monomer was 12, the surface tension of polycarboxylate polymeric surfactants was the lowest, which was 32.6 mN/m. The results of TG, DLS and TEM showed that with the increased of the alkyl chain length of the acrylate, the micellar size of polycarboxylate polymeric surfactants decreased regularly. Meanwhile, the foaming, wetting and emulsifying properties of polycarboxylate polymeric surfactants were positively correlated with the alkyl chain length of the acrylate. The dispersing ability of polycarboxylate polymeric surfactants for calcium carbonate was 101.5 mg/g, which can dispersed Fe2O3 fouling to less than 1 μm under the condition of 0.6 g/L.

Synthesis and evaluation of a new polymeric scale inhibitor with multiple scale inhibition properties

In this article, the monomers epoxy succinic acid (ESA) and maleic acid ethanolamine (PTA) were prepared, and then the terpolymer scale inhibitor P(ESA-AA-PTA) was synthesized by aqueous solution polymerization using ESA, PTA, and acrylic acid (AA) as monomers. The structures of the synthesized monomers and polymers were characterized by FTIR. The optimum synthesis conditions of the terpolymer were obtained by static scale inhibition experiment, and the effects of the amount of scale inhibitor, test temperature, test time, and solution pH on the inhibition performance of the four scales, CaCO3, CaSO4, BaSO4, and SrSO4, were discussed. The results showed that the best CaCO3 scale inhibition efficiency was 85% when the molar ratio of ESA:AA:PTA was 1:1:0.5, the initiator dosage was 10 wt%, the polymerization time was 3.5 hours and the polymerization temperature was 95 °C. In the optimum water environment, the scale inhibition efficiency of CaCO3 scale and CaSO4 scale reached 100%, BaSO4 scale could reach 75% and SrSO4 scale could reach 54%. P(ESA-AA-PTA) had better scale inhibition properties than the majority of commercially available oilfield scale inhibitors. SEM and XRD results showed that the addition of P(ESA-AA-PTA) scale inhibitor hindered the growth of crystals and made the microscopic morphology of scale samples changed.

Covalent Inactivation of Mycobacterium tuberculosis Isocitrate Lyase by cis-2,3-Epoxy-Succinic Acid.

The isocitrate lyases (ICL1/2) are essential enzymes of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis. At present, no ICL1/2 inhibitors have progressed to clinical evaluation, despite extensive drug discovery efforts. Herein, we surveyed succinate analogs against ICL1 and found that dicarboxylic acids constrained in their synperiplanar conformations, such as maleic acid, comprise uncompetitive inhibitors of ICL1 and inhibit more potently than their trans-isomers. From this, we identified cis-2,3 epoxysuccinic acid (cis-EpS) as a selective, irreversible covalent inactivator of Mtb ICL1 (kinact/Kinact= (5.0 ± 1.4) × 104 M-1 s-1; Kinact = 200 ± 50 nM), the most potent inactivator of ICL1 yet characterized. Crystallographic and mass spectrometric analysis demonstrated that Cys191 of ICL1 was S-malylated by cis-EpS, and a crystallographic "snapshot" of inactivation lent insight into the chemical mechanism of this inactivation. Proteomic analysis of E. coli lysates showed that cis-EpS selectively labeled plasmid-expressed Mtb ICL1. Consistently, cis-EpS, but not its trans-isomer, inhibited the growth of Mtb under conditions in which ICL function is essential. These findings encourage the development of analogs of cis-2,3-epoxysuccinate as antituberculosis agents.

Synthesis and Application of a Phosphorous-Free and Non-Nitrogen Polymer as an Environmentally Friendly Scale Inhibition and Dispersion Agent in Simulated Cooling Water Systems.

A novel phosphorus-free and non-nitrogen scale inhibition and dispersion agent was synthesized from epoxysuccinic acid (ESA), itaconic acid (IA), and sodium methyl propylene sulfonate (SMAS). It was characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), and elemental analysis, and its molecular weight and distribution were determined by gel permeation chromatography (GPC). Static experimental methods were used to evaluate the scale inhibition against CaCO3, Ca3(PO4)2, and CaSO4. The dispersion ability was evaluated by measuring the dispersive property of iron oxide. By observing the morphology of the CaCO3 scale, the scale inhibition mechanism was discussed. The results showed that when the ratio of raw materials (ESA/IA/SMAS) was 10:10:5, the scale inhibition rate of CaCO3 and CaSO4 reached 100% with the dosages of 20 and 10 mg/L, respectively. In addition, the scale inhibition rate against Ca3(PO4)2 was up to 96.64% with a dosage of 100 mg/L. The property of dispersing iron oxide exhibited the best results with 50 mg/L of the agent. On the 21st day, the biodegradation rate reached 63.33%. This polymer was an environmentally friendly antiscale and dispersant with good scale inhibition and biodegradability.

Effectiveness of Green Additives vs Poly(acrylic acid) in Inhibiting Calcium Sulfate Dihydrate Crystallization

ABSTRACT: The effects that 20 ppm poly(epoxysuccinic acid) (PESA), poly(aspartic acid) (PASP), and two poly(acrylic acid) (PAA) compounds with molecular weights of ∼2000 and ∼100000 have on the crystallization of gypsum were evaluated at 21 °C byin situ UV−vis spectrophotometry. XRD and SEM were utilized for phase and morphological studies, while the way these additives are associated with the final gypsum crystals was evaluated by XPS. The comparison showed that PASP performed far better than the other antiscalants as it completely inhibited the formation of gypsum. In contrary, the presence of the low molecular weight PAA decreased the rate of crystallization far more than the larger molecular weight PAA. When the pH in the reacting solution was switched from ∼4 to∼7, the efficiency of the low molecular weight PAA in inhibiting gypsum formation increased, while in the presence of the higher molecular weight PAA the opposite effect was observed.

A Novel Eco-Friendly Scale and Corrosion Inhibitor Modified by β-Cyclodextrin

A polymer, β-MEA, was synthesised from β-cyclodextrin (β-CD), 3-chloro-2-methylpropene (MAC), epoxysuccinic acid (ESA), and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) with a (NH4)2S2O8-NaHSO3 redox initiator system by aqueous solution radical polymerisation. β-MEA was characterised by means of IR spectroscopy, time-of-flight mass spectrometry, gel permeation chromatography, and thermogravimetric analysis. Its structure, molecular weight, thermal stability, scale and corrosion inhibition performance and mechanism were investigated. The results verified that β-MEA achieves a better scale inhibition efficiency for BaSO4 compared with poly(aspartic acid) (PASP) (100 % cf. 94.9 % at a concentration of 20 mg L−1) and a better corrosion inhibition efficiency of N80 carbon steel in saline water compared with PESA (91.2 % cf. 79.7 % at a concentration of 1 g L−1). The BaSO4 was characterised by scanning electron microscopy (SEM) and X-ray diffraction to investigate the crystal morphology of the scale. Primary research on the mechanism for corrosion inhibition was carried by SEM-chemical analysis.

Design, synthesis, and screen of cathepsin K inhibitors

Abstract We synthesized a series of epoxysuccinic acid derivatives and evaluated their in vitro cathepsin K inhibitory activity The screening results show that the potency of compounds 9e , 9d , 9p , 9j and 9k (IC 50 ≤ 0.005 μmol/L) were equal to or greater than that of the lead compound 9a . Less hydrophobic compounds showed weaker potency, which can be explained by the hydrophobic nature of the cathepsin K binding pockets.

Synthesis and properties of a MEAS quadripolymer scale inhibitor

A novel quadripolymer scale inhibitor was prepared from maleic anhydride (MA), epoxy succinic acid sodium (ESAS), acrylamide (AM) and sodium allyl sulphonate (SAS), and the polymerisation was initiated by persulphate ammonium. This study determined the optimal synthesis conditions for the scale inhibitor by the orthogonal test, and investigated scale inhibitor dosage, systematic pH values and temperature on the scale inhibitor anti-scaling properties. The results showed that the optimal conditions of synthesis were as follows: the mass ratio of persulphate ammonium to total monomer was 15%, the monomer molar ratio for n(MA):n(ESAS):n(AM):(SAS) was 1:1:0.6:1, the reaction temperature was 90°C and the reaction time was 3 h. When the temperature was 50°C, the pH value was 10, the scale inhibitor dosage was 20 mg/L and the calcium carbonate anti-scaling rate was 96%. The infrared spectra indicated that the synthetic copolymer contained the target functional groups. Scanning electron micrographs showed that the quadripolymer scale inhibitor mainly played roles in complexation and solubilisation. The practical application of the inhibitor led to an improved anti-scaling effect.

Research on Synthesis Regularity of Epoxysuccinic Acid

The yield of epoxysuccinic acid was obtained by determining the content of unreacted maleic anhydride and tartaric acid as a by-product in synthesis system. This method could calculate the yield of epoxysuccinic acid precisely and overcome the disadvantage of obtaining inpure product by recrystallization method. Epoxysuccinic Acid was synthesized using maleic anhydride as raw material, hydrogen peroxide as oxidizer and tungstate as catalyst. The effects of reaction temperature, reaction time, ratio of materials, dosage of oxidizer and catalyst on epoxidation and hydrolysis reaction was investigated. The results showed that the yield of epoxysuccinic acid was 88% when the reaction conditions were as follows: reaction temperature 65°C, reaction time 1.5h, catalyst dosage 3%(based on mass of maleic anhydride), molar ratio of sodium hydrate to maleic anhydride 2:1, mass ratio of hydrogen peroxide to maleic anhydride 1:1.

Synthesis and Properties of the ESA/AMPS Copolymer

A copolymer was prepared from epoxy succinic acid (ESA) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS). The structure of the ESA/AMPS copolymer was characterized by means of FTIR. The performances of scale inhibition, dispersion and biodegradability of the ESA/AMPS copolymer were studied. The results showed that the scale inhibition performance of the ESA/AMPS copolymer on calcium phosphate and dispersing performance on ferric oxide were much better than PESA. The scale inhibition rate on calcium carbonate was 85% when the ESA/AMPS copolymer was 8mg/L. The scale inhibition rate on calcium phosphate was 65% when the ESA/AMPS copolymer was 30mg/L. The ESA/AMPS copolymer had good biodegradation performance and biodegradation rate could reach 65% after 28 days.

ChemInform Abstract: A Synthesis of a γ-Azetidinyl-β-hydroxy-α-amino Acid Derivative, a Key Intermediate for the Synthesis of Mugineic Acid.

Abstract The γ-azetidinyl-β-hydroxy-α-amino acid derivative 2, a key intermediate for the total synthesis of mugineic acid (1), was stereoselectively prepared from readily available (2R,3R)-epoxysuccinic acid (3).

Isolation and characterization of a new bacterium capable of biotransformingcis-epoxysuccinic acid to d(−)-tartaric acid

A bacterial strain 1-3 capable of enantioselectively hydrolyzing cis-epoxysuccinic acid to D(-)-tartaric acid was isolated from soil. Phenotypic characteristics, Biolog GN test and phylogenetic analysis of strain 1-3 indicated that it belongs to the genus Bordetella. cis-Epoxysuccinic acid could be used as a carbon source and inducer for production of cis-epoxysuccinic acid hydrolase. After the purification of the enzymatic biotransformed product, a colorless and scentless crystal was obtained, which was confirmed to be the tartaric acid with laevorotatory optical rotation by the (1)H nuclear magnetic resonance spectrum and optical rotation analysis.

METABOLIC REGULATION OF FUNGAL REPRODUCTION AND THEIR SECONDARY METABOLITES

Eurotium repens (Anamorph Aspergillus repens) was isolated from spoiled fruit (Fig). It reproduced sexually in presence of different sucrose concentrations up to 50% (w/v) (water activity, 0.79). While at high sucrose concentration 60% (w/v) (water activity, 0.75) it reproduced asexually. The concentrations of all detected amino acids were higher in teleomorph stage than anamorph stage except glycine. While a-aminoadipic acid and alanine were detected in teleomorph only. The extracellular secondary metabolites produced by teleomorph and anamorph stages were variable and different except epoxysuccinic acid and 2-pyruvylamino benzamide were produced by the two stages. Glycine, arginine and calcium chloride unlike glutamic acid, aspartic acid and alanine plays an important role in the induction of teleomorph stage formation at a concentration of 60 % (w/v) sucrose.

A Convenient Preparation of Enantiomerically Pure Esters of trans- Epoxysuccinic Acid

We report herein a new and efficient four-step method for the stereoselective conversion of (-) diethyl (D)- and (+) diethyl (L)-tartrate into diethyl (2S,3S)-(+)-2,3-epoxysuccinate and diethyl (2R,3R)-(-)-2,3- epoxysuccinate respectively. We also applied this synthetic method to prepare a C-2 symmetric epoxide, a key chiral intermediate, employed in the total synthesis of natural products. Keywords: Cyclic orthoformate, bromohydrin, enantiomers, epoxide

Density functional complexation study of metal ions with poly(carboxylic acid) ligands. Part 2. Poly(acrylic acid- co-maleic acid), poly(methyl vinyl ether- co-maleic acid), and poly(epoxy succinic acid)

We have studied metal ion complexation with poly(carboxylic acid) ligands using density functional methods and a continuum-solvation model (COSMO). Geometry optimisations have been carried out for metal complexes of poly(acrylic acid- co-maleic acid), poly(methyl vinyl ether- co-maleic acid), and poly(epoxy succinic acid) oligomers. The complexation energies for Mg 2+, Ca 2+, Mn 2+, and Fe 3+ have been calculated and they have been corrected with previously determined metal specific correction parameters. The most effective ligand for all the metal ions was found to be poly(epoxy succinic acid). With Ca 2+, poly(epoxy succinic acid) was found to form 6-coordinated complex with three metal-coordinating carboxylate oxygen, two ether oxygens, and one hydroxyl oxygen atom. All the other metals favoured 5-coordinated complexation geometry with four metal-coordinating carboxyl oxygens and one ether oxygen atom.

A Novel Highly Copper(ll)-selective Chelating Ion Exchanger Based on Poly(Glycidyl Methacrylate-coethylene Dimethacrylate) Beads Modified with Aspartic Acid Derivative

Anchoring the hydroxyaspartic acid onto poly(glycidyl methacrylate-co-ethylene dimethacrylate) (poly(GMA-co-EDMA)) beads or epoxysuccinic acid onto ammoniummodified poly(GMA-co-EDMA) beads resulted in a novel chelating resin, which contained up to 0.37 mmol of the ligand per gram of resin. Batch extraction experiments showed a very high selectivity for Cu2+ over Zn2+ and Cd2+ ions in buffered solutions under competitive conditions.

A novel highly copper(II)‐selective chelating ion exchanger based on poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) beads modified with aspartic acid derivative

AbstractAnchoring the hydroxyaspartic acid onto poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) (poly(GMA‐co‐EDMA)) beads or epoxysuccinic acid onto ammonium‐modified poly(GMA‐co‐EDMA) beads resulted in a novel chelating resin, which contained up to 0.37 mmol of the ligand per gram of resin. Batch extraction experiments showed a very high selectivity for Cu2+ over Zn2+ and Cd2+ ions in buffered solutions under competitive conditions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 913–916, 2001

Inhibition of cysteine proteases by peptides containing aziridine-2,3-dicarboxylic acid building blocks.

Mammalian cysteine proteases of the papain superfamily are interesting targets for the development of new drugs against diseases connected to abnormal degradation of muscle or bone proteins. The high nucleophilicity of the active site of these proteases as well as the characteristics of the well-known epoxysuccinic acid derived cysteine protease inhibitors provided a basis for the design of new types of selective and irreversible inhibitors for these enzymes. We designed and synthesized a novel class of peptidic cysteine protease inhibitors containing aziridine-2,3-dicarboxylic acid as electrophilic amino acid. Three types of aziridinyl peptides that differ in the position of the aziridine building block within the peptide chain have been synthesized and tested as inhibitors of several cysteine proteases. Remarkable differences could be observed between the three types of inhibitors concerning their activity, stereospecificity, pH dependency of inhibition, and selectivity between different cysteine proteases, respectively, indicating that different binding modes of the three types of inhibitors in respect to their orientation in the S and S' binding sites of the enzymes may be present.

Oxidation of defined antigens allows protein unfolding and increases both proteolytic processing and exposes peptide epitopes which are recognized by specific T cells.

The participation of oxidative mechanisms in major histocompatibility complex (MHC) class II-restricted antigen presentation was studied in vitro. In general, antigen processing is inhibited when peritoneal macrophages (MO) are incubated with scavengers of reactive oxygen intermediates (ROI): mannitol (an.OH scavenger), dimethylurea (DMTU, which reacts with H2O2 and HOCl) and NCO-700 (an epoxysuccinic acid derivative which inhibits oxidant production by activated phagocytes and can scavenge reactive oxygen species in both NaOCl and hypoxanthine (XOD) systems). However, neither rotenone and antimycins (inhibitors of O-2 production at the NADH dehydrogenase and ubiquinone-cytochrome b regions, respectively) nor aminoguanidine (an inducible nitric oxide synthase inhibitor) impaired antigen presentation, thus indirectly discarding the participation of mitochondrial oxidation and reactive nitrogen intermediates (RNI) in antigen processing. ROI scavengers do not inhibit the MHC class II-restricted presentation of antigens that need processing but have their disulphide bonds reduced. It can be shown that oxidation of protein antigens (either by chlorination or performic acid treatment) allow protein unfolding and enhance both processing and exposure of immunogenic epitopes to specific T cells.