- Thermodynamic Parameters of Coupled Chemical Reactions from Temperature Jump Relaxation Amplitudes
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Equations describing the temperature jump amplitudes associated with a system of two coupled reactions (TRIS - phenol red) as well as the ternary system (Mg(2+) - iminodiacetic acid - phenol red) are presented.The thermodynamic parameters calculated from experimentally measured temperature perturbation amplitudes using a multiparametric curve fitting procedure are found to be in good agreement with those determined from pH- and constant rate thermometric titrations.For phenol red, pKI = 7.55, ΔHI = 3.45 kcal, and for Mg(2+) iminodiacetic acid , logKM = 2.84, ΔHM = 3.25 kcal, were obtained.It is shown that this method can be used to determine accurate thermodynamic enthalpy changes over a narrow temperature interval of less than 1.0 deg C from a single experiment requiring about 50 μl of sample solution.
- Ushio, Hidetoshi,Trimm, Harold H.,Patel, Ramesh C.,Zemany, Michael D.
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- Biotransformation of iminodiacetonitrile to iminodiacetic acid by Alcaligenes faecalis cells immobilized in ACA-membrane liquid-core capsules
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Biotransformation of iminodiacetonitrile (IDAN) to iminodiacetic acid (IDA) was investigated with a newly isolated Alcaligenes faecalis ZJUTBX11 strain showing nitrilase activity in the immobilized form. To reduce the mass transfer resistance and to increase the toleration ability of the microorganisms to the toxic substrate as well as to enhance their ability to be reused, encapsulation of the whole cells in alginate-chitosan-alginate (ACA) membrane liquid-core capsules was attempted in the present study. The optimal pH and temperature for nitrilase activity of encapsulated A. faecalis ZJUTBX11 cells were 7.5 C and 35 C, respectively, which is consistent with free cells. Based on the Michaelis-Menten model, kinetic parameters of the conversion reaction with IDAN as the substrate were: K m = (17.6 ± 0.3) mmol L-1 and V max = (97.6 ± 1.2) μmol min-1 g -1 of dry cell mass for encapsulated cells and (16.8 ± 0.4) mmol L-1 and (108.0 ± 2.7) μmol min-1 g -1 of dry cell mass for free cells, respectively. After being recycled ten times, the whole cells encapsulated in ACA capsules still retained 90 % of the initial nitrilase activity while only 35 % were retained by free cells. Lab scale production of IDA using encapsulated cells in a bubble column reactor and a packed bed reactor were performed respectively.
- Zhang, Jin-Feng,Liu, Zhi-Qiang,Zhang, Xin-Hong,Zheng, Yu-Guo
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- Highly efficient and stable bicomponent cobalt oxide-copper catalysts for dehydrogenation
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Cu/Co3O4-ZrO2 catalyst was synthesized by a simple co-precipitation method, and its self-oxidation behavior after reduction reduced the particle size of Co3O4. Cu/Co3O4-ZrO2 demonstrated a high performance during the dehydrogenation of diethanolamine, reaching a 96% yield of iminodiacetic in 30 min. The catalyst was characterized by XRD, XPS, TEM, SEM, and H2-TPR. The results showed that strong Cu-oxide interactions, the co-catalysis of biactive components, and the higher number of oxygen vacancies of Cu/Co3O4-ZrO2 were responsible for the enhanced catalytic activity during diethanolamine dehydrogenation. Co3O4 particles improved the dispersion and stability of Cu NPs and inhibited the sintering of loaded Cu NPs.
- Chen, Li,Duan, Zhengkang,Guo, Dongjie,Qiu, Tian,Ren, Shiyu,Wang, Yongsheng,Wu, Yingying,Xu, Weixiang,Zhang, Xinping
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- A ZrO2-RGO composite as a support enhanced the performance of a Cu-based catalyst in dehydrogenation of diethanolamine
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The sintering resistance of supported Cu nanoparticle (NP) catalysts is crucial to their practical application in the dehydrogenation of diethanolamine (DEA). In this paper, co-precipitation, hydrothermal synthesis, and sol-gel condensation are used to form a new support material through chemical bonding between graphene oxide and ZrO2. The composite carriers prepared by the three methods are mixed with copper nitrate and ground using a ball mill. A series of Cu/ZrO2-reduced graphene oxide (RGO) composites were prepared by calcination under nitrogen at 450 °C for 3 h and hydrogen reduction at 250 °C for 4 h. The conversion of DEA to iminodiacetic acid (IDA) reached 96% with the Cu/ZrO2-RGO catalyst prepared by hydrothermal synthesis. The conversion rate of DEA is more than 80% following the reuse of the CZG-2 catalyst for twelve cycles. The various physicochemical characterization techniques show that the Cu/ZrO2-RGO layered and wrinkled nanostructures can improve catalytic stability and suppress the sintering of the supported Cu NPs during the catalytic dehydrogenation of diethanolamine. A synergistic effect between the RGO and the Cu nanoparticles is observed. The Cu nanoparticles with RGO have a better dispersibility, and a new nano-environment is created, which is the key to improving the efficiency of diethanolamine dehydrogenation. These new Cu/ZrO2-RGO catalysts show increased durability compared to commercially produced Cu/ZrO2 catalysts and show promise for practical applications involving diethanolamine dehydrogenation.
- Wang, Yongsheng,Zhao, Zhenzhen,Zhao, Yunlu,Lan, Xiaolin,Xu, Weixiang,Chen, Li,Guo, Dongjie,Duan, Zhengkang
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- A Zinc(II) Photocage Based on a Decarboxylation Metal Ion Release Mechanism for Investigating Homeostasis and Biological Signaling
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Metal ion signaling in biology has been studied extensively with ortho-nitrobenzyl photocages; however, the low quantum yields and other optical properties are not ideal for these applications. We describe the synthesis and characterization of NTAdeCage, the first member in a new class of Zn2+ photocages that utilizes a light-driven decarboxylation reaction in the metal ion release mechanism. NTAdeCage binds Zn2+ with sub-pM affinity using a modified nitrilotriacetate chelator and exhibits an almost 6 order of magnitude decrease in metal binding affinity upon uncaging. In contrast to other metal ion photocages, NTAdeCage and the corresponding Zn2+ complex undergo efficient photolysis with quantum yields approaching 30 %. The ability of NTAdeCage to mediate the uptake of 65Zn2+ by Xenopus laevis oocytes expressing hZIP4 demonstrates the viability of this photocaging strategy to execute biological assays. Light-driven metal release: A photodecarboxylation reaction has been exploited to design a photocaged complex for Zn2+ with superior properties compared to other caged metal complexes. The photocage has been used to control the uptake of Zn2+ in frog oocytes expressing a human zinc transport protein.
- Basa, Prem N.,Antala, Sagar,Dempski, Robert E.,Burdette, Shawn C.
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- Expanding the repertoire of nitrilases with broad substrate specificity and high substrate tolerance for biocatalytic applications
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Enzymatic conversion of nitriles to carboxylic acids by nitrilases has gained significance in the green synthesis of several pharmaceutical precursors and fine chemicals. Although nitrilases from several sources have been characterized, there exists a scope for identifying broad spectrum nitrilases exhibiting higher substrate tolerance and better thermostability to develop industrially relevant biocatalytic processes. Through genome mining, we have identified nine novel nitrilase sequences from bacteria and evaluated their activity on a broad spectrum of 23 industrially relevant nitrile substrates. Nitrilases from Zobellia galactanivorans, Achromobacter insolitus and Cupriavidus necator were highly active on varying classes of nitriles and applied as whole cell biocatalysts in lab scale processes. Z. galactanivorans nitrilase could convert 4-cyanopyridine to achieve yields of 1.79 M isonicotinic acid within 3 h via fed-batch substrate addition. The nitrilase from A. insolitus could hydrolyze 630 mM iminodiacetonitrile at a fast rate, effecting 86 % conversion to iminodiacetic acid within 1 h. The arylaliphatic nitrilase from C. necator catalysed enantioselective hydrolysis of 740 mM mandelonitrile to (R)-mandelic acid in 4 h. Significantly high product yields suggest that these enzymes would be promising additions to the suite of nitrilases for upscale biocatalytic application.
- Rayavarapu, Pratima,Shah, Shikha,Sunder, Avinash Vellore,Wangikar, Pramod P.
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p. 289 - 296
(2020/05/18)
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- A METHOD OF IMINODIACETIC ACID
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According to the present invention, a method for producing iminodiacetic acid comprises the following steps: (S1) hydrolyzing an aqueous solution of iminodiacetonitrile and calcium hydroxide; (S2) neutralizing the aqueous solution obtained in the step (S1) with hydrochloric acid; (S3) adding alcohol to the aqueous solution obtained in the step (S2) to produce an iminodiacetic acid precipitate; and (S4) filtering the precipitate produced in the step (S3) to obtain iminodiacetic acid. According to the present invention, it is possible to produce iminodiacetic acid at high purity and high yield.COPYRIGHT KIPO 2018
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Paragraph 0027; 0042-0044
(2018/06/29)
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- Synthesis of Deuterated or Tritiated Glycine and Its Methyl Ester
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Abstract: Heating glycine (Gly) and methyl glycinate (GlyOCH3) supported on 5% Pd/C or 5% Pt/C in a deuterium or tritium gas atmosphere gave the isotope-labeled products. The experiments were carried out at 180°C for 10 min. The deuterium atom inclusion under these conditions averaged up to 1.8 atoms per molecule for Gly and up to 1.0 atom per molecule for GlyOCH3. The reaction with tritium gas gave labeled products with a specific radioactivity of 27–31 Ci/mmol for Gly and 18 Ci/mmol for GlyOCH3.
- Shevchenko,Andreeva,Nagaev, I. Yu.,Myasoedov
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p. 266 - 267
(2019/01/03)
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- MANUFACTURING METHOD OF AMINOCARBOXYLIC ACID SALT
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PROBLEM TO BE SOLVED: To provide a manufacturing method of aminocarboxylic acid salt capable of suppressing and inhibiting generation of fastening of a coloring component in a reaction liquid containing the aminocarboxylic acid salt manufactured by oxidation dehydrogenation of amino alcohol in the presence of a copper-containing catalyst or capable of suppressing and inhibiting production of precipitate during manufacturing the aminocarboxylic acid from aminocarboxylic acid salt. SOLUTION: There is provided a manufacturing method for aminocarboxylic acid salt including oxidation dehydrogenation of amino alcohol in the presence of a copper-containing catalyst to obtain a reaction product and removing the copper-containing catalyst from the reaction product to obtain a reaction liquid containing aminocarboxylic acid salt having limitation of the total content (in terms of metals) of silicon (Si), aluminum (Al) and iron (Fe) to 100 mass.ppm or less. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
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Paragraph 0076
(2017/06/15)
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- Iminodiacetic acid preparation method
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A method for preparing iminodiacetic acid is characterized by comprising the following steps: (A), hydrolyzing iminodiacetonitrile into iminodiacetic acid disodium salt solution by virtue of sodium hydroxide; (B) adding ammonium sulfate or ammonium bisulfate into the hydrolysate to reach a certain pH value, neutralizing excessive sodium hydroxide and part of iminodiacetic acid disodium salt, and simultaneously recycling the produced ammonia so as to prepare ammonia water or liquid ammonia; and (C), adding sulfuric acid to regulate the pH value, cooling for crystallizing, separating so as to obtain iminodiacetic acid, and concentrating the filtrate to separate sodium sulfate to be used in the reaction in the next batch. The method for preparing iminodiacetic acid according to the claim 1 is characterized in that the pH value in the step (B) is 8-10. 3. The method for preparing iminodiacetic acid according to the claim 2 is characterized in that the pH value in the step (B) is 9.0-9.5. The method for preparing iminodiacetic acid according to any one of the claims 1-3 is characterized in that the pH value in the step (C) is 2.0-2.5.
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Paragraph 0029-0030
(2017/06/27)
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- A method for synthesizing pmida (by machine translation)
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The invention discloses a synthesis method of N-(Phosphonomethyl) iminodiacetic acid (PMIDA) using iminodiacetonitrile as the raw material. The method comprises the following steps: using mixed acid as a hydrolytic reagent, hydrolyzing the iminodiacetonitrile in the mixed acid water solution to obtain acid salt of the iminodiacetic acid, and then performing the condensation reaction of the hydrolyzation solution with phosphorous acid and formaldehyde at the presence of hydrochloric acid to obtain the N-(Phosphonomethyl) iminodiacetic acid, wherein the mixed acid is hydrochloric acid and sulfuric acid, or hydrochloric acid and orthophosphorous acid. According to the invention, the mixed acid is used as a hydrolytic reagent; meanwhile, high temperature and high pressure are adopted to enable the hydrolyzation to be more thorough; at the same time, no waste gas is emitted; and the periodic time of the whole synthesis process is short, the operation is simple, the utilization ratio of the raw materials is high, the side product is few, energy consumption is low and the three wastes are less.
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Paragraph 0028; 0029
(2017/01/17)
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- Biotransformation of iminodiacetonitrile to iminodiacetic acid by Alcaligenes faecalis cells immobilized in ACA-membrane liquid-core capsules
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Biotransformation of iminodiacetonitrile (IDAN) to iminodiacetic acid (IDA) was investigated with a newly isolated Alcaligenes faecalis ZJUTBX11 strain showing nitrilase activity in the immobilized form. To reduce the mass transfer resistance and to increase the toleration ability of the microorganisms to the toxic substrate as well as to enhance their ability to be reused, encapsulation of the whole cells in alginate-chitosan-alginate (ACA) membrane liquid-core capsules was attempted in the present study. The optimal pH and temperature for nitrilase activity of encapsulated A. faecalis ZJUTBX11 cells were 7.5°C and 35°C, respectively, which is consistent with free cells. Based on the Michaelis-Menten model, kinetic parameters of the conversion reaction with IDAN as the substrate were: K m = (17.6 ± 0.3) mmol L-1 and V max = (97.6 ± 1.2) μmol min-1 g-1 of dry cell mass for encapsulated cells and (16.8 ± 0.4) mmol L-1 and (108.0 ± 2.7) μmol min-1 g-1 of dry cell mass for free cells, respectively. After being recycled ten times, the whole cells encapsulated in ACA capsules still retained 90 % of the initial nitrilase activity while only 35 % were retained by free cells. Lab scale production of IDA using encapsulated cells in a bubble column reactor and a packed bed reactor were performed respectively.
- Zhang, Jin-Feng,Liu, Zhi-Qiang,Zhang, Xin-Hong,Zheng, Yu-Guo
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- Nitrilase activity screening on structurally diverse substrates: Providing biocatalytic tools for organic synthesis
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A high-throughput screening of candidate nitrilases against 25 structurally diverse substrates allowed us to create a wide collection of 125 experimentally validated nitrilases. The enzymes were selected by genomic approach from 700 diverse prokaryotic species and one metagenome as representative of the nitrilase family diversity. The enzymatic screening of this collection expands the biocatalytic toolbox for chemical synthesis by providing a large number of tested nitrilases with their assigned substrates. Three examples illustrate the synthetic potential of our enzyme collection. The syntheses of carboxylic acid building blocks, a β-substituted phenylpropanoic acid, a cyclic γ-keto carboxylic acid and a mononitrile monocarboxylic acid, were achieved from the corresponding nitrile substrates, using three new nitrilases (two from Sphingomonas wittichii and one from Syntrophobacter fumaroxidans). Improvements of nitrilase activities through the optimization of reaction parameters and the preparative biocatalytic synthesis are presented for these three examples. Copyright
- Vergne-Vaxelaire, Carine,Bordier, Franck,Fossey, Aurelie,Besnard-Gonnet, Marielle,Debard, Adrien,Mariage, Aline,Pellouin, Virginie,Perret, Alain,Petit, Jean-Louis,Stam, Mark,Salanoubat, Marcel,Weissenbach, Jean,De Berardinis, Veronique,Zaparucha, Anne
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p. 1763 - 1779
(2013/07/19)
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- Raney copper
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Raney copper which is doped with at least one metal from the group comprising iron and/or noble metals is used as a catalyst in the dehydrogenation of alcohols.
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- The reactions of ozone with tertiary amines including the complexing agents nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA) in aqueous solution
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Using the stopped-flow technique, the rate constants of the reaction of ozone with a number of amines have been determined. While the protonated amines do not react with ozone, the free amines react with rate constants of around 106 dm3 mol-1 s-1 in the case of tertiary and secondary amines, while primary amines react more slowly. Mono-protonated EDTA reacts only with k = 1.6 × 105 and mono-protonated 1,4-diazabicyclo[2.2.2]octane (DABCO) with k = 3.5 × 103 dm3 mol-1 s-1. In aqueous solution, tertiary amines react with ozone mainly by forming the aminoxide and singlet dioxygen [O2(1Δg)] and to a lesser extent the secondary amine and the corresponding aldehyde, a reaction which can be partially suppressed by tert-butyl alcohol. These data suggest that O-transfer [aminoxide plus O2(1Δg)] is in competition with an electron transfer which leads to the amine radical cation and an ozonide radical. In water, the latter gives rise to ·OH which further reacts with the amine (and ozone). The amine radical cation deprotonates at a neighboring carbon. The resulting radical adds dioxygen. Subsequent elimination of O2·- and hydrolysis of the Schiff-base thus formed leads to the secondary amine and the corresponding aldehyde. In its reaction with ozone, O2·- yields further ·OH. Their reaction with the amines leads to the same intermediate as the free-radical pathway of ozone does, i.e. induces a chain reaction. This is interfered with by tert-butyl alcohol at the OH-radical stage. When complexed to Fe(III), EDTA reacts only very slowly with ozone (k = 330 dm3 mol-1 s-1). This explains why EDTA is not readily removed by ozonation in drinking-water processing.
- Munoz, Florinella,Von Sonntag, Clemens
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p. 2029 - 2033
(2007/10/03)
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- Method of preparing amino carboxylic acids
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Process for the preparation of an N-acyl amino carboxylic acid by means of a carboxymethylation reaction. In this reaction, a reaction mixture is formed which contains a base pair, carbon monoxide, hydrogen and an aldehyde with the base pair comprising a carbamoyl compound and a carboxymethylation catalyst precursor. In a preferred embodiment, the carbamoyl compound and aldehyde are selected to yield an N-acyl amino carboxylic acid which is readily converted to N-(phosphonomethyl)glycine, or a salt or ester thereof.
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- METHOD FOR OBTAINING ACETIC ACID DERIVATIVES
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Method for obtaining acetic acid derivatives, such as glycin, IDA and NTA by dehydrogenation of mono-, di- and triethanolamine, respectively, in the presence of a Copper-Raney catalyst. Such method includes a step consisting in regenerating the catalyst spent in order to reuse it in successive reaction cycles. The regeneration method is comprised of the treatment of the spent catalyst with backflowing formic acid, filtering and repulping it with demineralized water and NaOH till the washing waters reach a sligthly alkaline value. The regenerated catalyst may be reused in successvie reaction cycles maintaining an average efficency of 87 %, that is to say of the same order of magnitude as when using a new catalyst.
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- PHOSPHONIUM AZA-YLDIID AS REAGENT FOR ONE-POT SYNTHESIS OF PHOSPHINIMINES WITH FUNCTIONAL N-SUBSTITUENTS.
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A new procedure for the one-pot synthesis of phosphinimines with functional N-substituents using the alkylation of phosphonium aza-yldiid 1 with α-bromo esters or the direct introduction of phosphorus and sulfur groups.
- Cristeau, Henri-Jean,Manginot, Eric,Torreilles, Eliane
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p. 347 - 350
(2007/10/02)
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- Amine dealkylation process
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Amino acids can be produced from suitable tertiary and secondary amines by dealkylation using an alkali metal hydroxide.
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- Polypeptides/chelating agent nasal compositions having enhanced peptide absorption
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Disclosed herein are nasal spray compositions and methods for enhancing polypeptide absorption across nasal membranes comprising a chelating agent and a polypeptide in a pharmaceutically acceptable excipient.
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- The Ion-exchange Chromatography of Imino Derivatives of Glycine
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The resolution of the six imino derivatives of glycine (Gly) by ion-exchange chromatography is described.The imino compounds included iminodiacetonitrile (1), iminodiacetamide (2), iminodiacetic acid (3), α-(cyanomethylamino)acetamide (4), α-(cyanomethylamino)acetic acid (5), and α-(carbamoylmethylamino)acetic acid (6).A mixture of 1-6 was chromatographed along with Gly, glycinamide, aminoacetonitrile, and NH3 with an automatic amino acid analyzer using Aminex A-4 resin column (0.25φ x 50 cm) and sodium citrate buffers.When the initial buffer of pH 3.25 was changed to pH 6.50 15 min after beginning the analysis, these ten components were completely resolved.The analysis was completed in about 4.5 h.The stability of 1, 4, and 5 in aqueous media at room temperature was also studied.
- Kawashiro, Katsuhiro,Morimoto, Shiro,Yoshida, Hideyuki
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p. 792 - 795
(2007/10/02)
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- Synthesis of Strombine. A New Method for Monocarboxymethylation of Primary Amines
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Many common methods for monocarboxymethylation of primary amines give various amounts of dialkylated by-products.In this work the reaction of two equivalents of glyoxilic acid with representative primary aliphatic and aromatic amines, as well as with amino acids and a dipeptide, is shown to give only the N-(carboxymethyl)-N-formyl derivative of the amine under mild conditions in carboxylic acid solvents.Hydrolysis then produces the monocarboxymethylated primary amine in good to exellent overall yield.Proof that the intermediate product is not obtained via the Leuckart reaction is given.
- Kihlberg, Jan,Bergman, Rolf,Wickberg, Boerje
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p. 911 - 916
(2007/10/02)
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- The iron(III)-catalyzed oxidation of EDTA in aqueous solution
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At temperatures above 100 deg C iron(III) oxidizes coordinated EDTA to ethylenediaminetriacetic acid in aqueous solution in the absence of molecular oxygen.The reaction proceeds with an activation energy of 28.6 kcal/mol, and its rate is directly proportional to the concentration of Fe(III) and inversely proportional to pH.At 125 deg C, the halflife of Fe(III) in the presence of excess EDTA is about 3 h at pH 9.3, but increases to >70 h at pH 5.4.The reaction is stoichiometric and no other reaction products or by-products were detected by nmr, gc, and gc - mass spectroscopy.In the presence of oxygen iron catalyzes quantitative oxidation of ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) to ethylenediaminetriacetic acid.The copper(II)-EDTA chelate undergoes a similar reaction but higher temperatures (>/=170 deg C) are required.Iron(III) also oxidizes nitrilotriacetic acid (NTA) to iminodiacetic acid (IDA) and glycine.The hydrolyzed species Fe(OH)EDTA is shown to be the reactive intermediate, and the well-known (Fe-EDTA)2O(4-) μ-oxo dimer is shown not to exist at elevated temperatures (above 100 deg C).Probable mechanisms are proposed for these reactions and comparisons are made with earlier work.
- Motekaitis, Ramunas J.,Martell, Arthur E.,Hayes, David,Frenier, Wayne W.
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p. 1999 - 2005
(2007/10/02)
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