- Ecotoxicity and biodegradation of phthalate monoesters
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Little is known about the fate and the effects of phthalic acid monoesters. Various of these monoesters ranging from n-butyl to isononyl monoester have been evaluated in respect to their biodegradation behaviour and their acute aquatic toxicity. All esters are readily biodegradable, achieving degradation rates of 90% and more. The acute toxicity values strongly depend on the carbon chain length of the alcohol moiety. The short chain specimen have LC/EC 50 around and above 100 mg/l, with values levelling off to around 30 mg/l for the isononyl monoester.
- Scholz, Norbert
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- Adjuvant and immuno-suppressive effect of six monophthalates in a subcutaneous injection model with BALB/c mice
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The prevalence of allergic airway diseases is rapidly increasing in Western Europe and North America. This increase in disease prevalence may be associated with environmental pollutants. The present study investigated the adjuvant and immuno-suppressive effect of a series of monophthalates which are considered to be important metabolites of commonly used phthalate plasticizers. The effects were studied in a screening model. Ovalbumin (OA), used as the model antigen, was injected subcutaneously in the neck region of BALB/cJ mice with or without one of the test substances, mono-n-butyl phthalate (MnBP), monobenzyl phthalate (MBnP), mono-n-octyl phthalate (MnOP), mono-2-ethylhexyl phthalate (MEHP), mono-iso-nonyl phthalate (MiNP) or mono-iso-decyl phthalate (MiDP). The levels of OA-specific IgE, IgG1 and IgG2a in sera were measured by ELISA. Immuno-suppressive effect, defined as a statistically significant reduction in IgE or IgG1 antibody production, was observed with MEHP (1000 μg/ml, IgE and IgG1), MnOP (1000 μg/ml, IgE and IgG1), MiNP (1000 μg/ml, IgE and 10 μg/ml, IgG1) and MiDP (100 μg/ml, IgE and IgG1). Adjuvant effect, defined as a statistically significant increase in IgE or IgG1 antibody level, occurred with MEHP (10 μg/ml, IgE), MnOP (100 μg/ml, and 10 μg/ml, IgG1) and MiNP (100 μg/ml, IgE). No statistically significant immune modulating effect was seen with MBnP and MnBP.
- Larsen, Soren Thor,Hansen, Jitka Stilund,Thygesen, Peter,Begtrup, Mikael,Poulsen, Otto Melchior,Nielsen, Gunnar Damgard
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- Involvement of a novel mouse hepatic microsomal esterase, ES46.5K, in the hydrolysis of phthalate esters
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ES46.5K, a novel esterase from mouse hepatic microsomes (Watanabe K., et al., Biochem. Mol. Biol. Int., 31, 25-30 (1993)), catalyzed hydrolysis of phthalate esters. ES46.5K and mouse hepatic microsomes hydrolyzed diethyl-, dibutyl-, diisobutyl-, dioctyl- and diethylhexyl phthalates, whereas dicyclohexyl- and dipbenyl phthalates having ring structure were not hydrolyzed by the enzymes. V(max) (μmol/min/mg protein)/K(m) (μM) ratios of ES46.5K for diethyl-, dibutyl-, diisobutyl-, dioctyl- and diethylhexyl phthalates were 291, 2786, 565, 51 and 57, respectively, while those of microsomes were 0.58, 0.83, 1.71, 0.05 and 1.10, respectively. The hydrolytic activity of ES46.5K was inhibited by diisopropylfluorophosphate and bis-p- nitrophenylphosphate. These results suggest that ES46.5K has high catalytic activity for phthalate esters and some role in the metabolism of phthalate esters in mice.
- Kayano, Yuichiro,Watanabe, Kazuhito,Matsunaga, Tamihide,Yamamoto, Ikuo,Yoshimura, Hidetoshi
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- Synthesis, crystal structure and Thermogravimetry of ortho-phthalic acid bridged coordination polymer of Copper(II)
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Coordination polymer of Cu(II) bridged by o-phthalic acid alone is not known. The reaction of CuCl2.2H2O with (2-butoxycarbonyl)benzoic acid yielded three dimensional coordination polymer bridged by o-phthalic acid. X-ray crystal structure shows structure with monoclinic P21/c space group. o-Phthalic acid molecules act as bridge between two Cu(II), one carboxylate binds to one Cu(II) as bidentate while the other carboxylate binds to another Cu(II) as monodentate. The four planar co-ordination positions of Cu(II) are satisfied by two chelated carboxylates while fifth and sixth co-ordination positions are satisfied by monodentate carboxylates. EPR and TGA of the coordination polymer are also reported. [Figure not available: see fulltext.]
- Sarma, Babita,Bharali, Saurav,Das, Diganta Kumar
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- Mechanism of testicular atrophy induced by di-n-butyl phthalate in rats. Part 5. Testicular iron depletion and levels of ferritin, haemoglobin and transferrin m the bone marrow, liver and spleen
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This study reports changes in levels of ferritin, haemoglobin and transferrin in the bone marrow, liver and spleen as an attempt to determine the causes of testicular iron depletion. A single oral dose of di-n-butyl phthalate (DBP) to male rats caused a sloughing of the germ cells (at 6 h) prior to testicular atrophy. Before the sloughing it was observed that DBP induced decreases both in the iron levels in the blood, bone marrow and testis and in haemoglobin (Hb) levels in the blood, bone marrow and spleen. Decrease in transferrin (Tf) levels was observed in the liver. Significant increases in ferritin and haemosiderin (Hs) levels were observed in the spleen and in the liver and spleen, respectively. In v;fro studies where mono-n-butyl phthalate (MBP) was incubated with liver homogenates, MBP caused both the decreases in Hb and Tf-bound iron levels and increases in Hs and Hs-iron levels. The present study proposes that the mechanism of testicular atrophy by DBP might be associated with both the iron release from Hb and/or Tf in the liver and spleen and the subsequent depletion of iron in the blood and testes.
- Fukuoka,Kobayashi,Hayakawa
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- Practical selective monohydrolysis of bulky symmetric diesters
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The highly efficient selective monohydrolysis reaction we previously reported has been applied to monohydrolysis of several bulkyl symmetric diesters, including diethyl esters, dipropyl esters, and dibutyl esters. A greater proportion of a polar aprotic co-solvent, DMSO, and aqueous KOH appear to help improve the reactivity of bulky diesters compared to the corresponding dimethyl esters. The procedure is mild and practical, yielding the corresponding half-esters in high yields under simple conditions.
- Shi, Jianjun,Niwayama, Satomi
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- Catalytic upcycling of PVC waste-derived phthalate esters into safe, hydrogenated plasticizers
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Recycling of end-of-life polyvinyl chloride (PVC) calls for solutions to deal with the vast amounts of harmful phthalate plasticizers that have historically been incorporated in PVC. Here, we report on the upcycling of such waste-extracted phthalate esters into analogues of the much safer diisononyl 1,2-cyclohexanedicarboxylate plasticizer (DINCH), via a catalytic one-pot (trans)esterification-hydrogenation process. For most of the virgin phthalates, Ru/Al2O3 is a highly effective hydrogenation catalyst, yielding >99% ring-hydrogenated products under mild reaction conditions (0.1 mol% Ru, 80 °C, 50 bar H2). However, applying this reaction to PVC-extracted phthalates proved problematic, (1) as benzyl phthalates are hydrogenolyzed to benzoic acids that inhibit the Ru-catalyst, and (2) because impurities in the plasticizer extract (PVC, sulfur) further retard the hydrogenation. These complications were solved by coupling the hydrogenation to an in situ (trans)esterification with a higher alcohol, and by pretreating the extract with an activated carbon adsorbent. In this way, a real phthalate extract obtained from post-consumer PVC waste was eventually completely (>99%) hydrogenated to phthalate-free, cycloaliphatic plasticizers. This journal is
- Bals, Sara,De Vos, Dirk E.,Diefenhardt, Thomas,Jain, Noopur,Marquez, Carlos,Schlummer, Martin,Windels, Simon
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p. 754 - 766
(2022/02/02)
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- Synthesis of New Dialkyl 2,2′-[Carbonyl bis (azanediyl)]dibenzoates via Curtius Rearrangement
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The 2-(alkylcarbonyl)benzoic acids obtained by esterification of phthalic anhydride are converted into azide derivatives: alkyl 2-[(azidocarbonyl)amino]benzoates and to ureas: dialkyl 2,2′-[carbonyl bis (azanediyl)]dibenzoates. These transformations were carried out using classical Curtius rearrangement conditions in the presence of diphenylphosphoryl azide (DPPA) in a basic medium, followed by hydrolysis. Subsequently, a final condensation reaction of these urea derivatives enabled us to obtain, for the first time, the new alkyl derivatives, alkyl 2-[2,4-dioxo-1,2-dihydroquinazolin-3(4 H)-yl]benzoates. All the new compounds obtained in satisfactory yields were characterized by 1H and 13C NMR, and by X-ray crystallographic analysis.
- Yassine, Hasna,Bouali, Jamila,Oumessaoud, Asmaa,Ourhzif, El Mahdi,Hamri, Salha,Hafid, Abderrafia,Khouili, Mostafa,Pujol, Maria Dolors
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p. 1971 - 1979
(2021/01/21)
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- Practical selective monohydrolysis of bulky symmetric diesters: Comparing with sonochemistry
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The conditions of the practical selective monohydrolysis of symmetric diesters we previously reported have been modified and applied to selective monohydrolysis of bulky symmetric diesters. While ultrasound is generally considered effective for two-phase reactions, its effect actually turned out to be rather marginal. Instead, use of a larger proportion of a polar aprotic co-solvent, DMSO, and aqueous KOH helped enhance the reaction rates and improve the yields of the half-esters. The reactions are simple, mild and practical without special devices.
- Shi, Jianjun,Zhao, Tian,Niwayama, Satomi
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p. 6815 - 6820
(2018/10/20)
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- A novel hydrogen-bonded silica-supported acidic ionic liquid: An efficient, recyclable and selective heterogeneous catalyst for the synthesis of diesters
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Abstract: In this study, two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles (SNPs) via hydrogen bonding. The materials were characterized by FT-IR, NMR, SEM, nitrogen physisorption measurement, TGA and acid-base titration. The catalytic activity of the prepared catalysts was investigated in the synthesis of phthalate, maleate and succinate diesters under solvent-free conditions. It was found that nanosilica@[HFDAIL] with higher availability of acidic sites and higher hydrophilicity was more efficient compared to the nanosilica@[SFDAIL]. Notably, nanosilica@[HFDAIL] catalyst has also demonstrated excellent selectivity for the diester product while the monoester product was predominant in the case of nanosilica@[SFDAIL] even after prolonged reaction time or higher catalyst loading. In addition, the nanosilica@[HFDAIL] catalyst could be separated by simple filtration and reused several times without any significant loss of catalytic performance, but a remarkable decrease in activity was observed for nanosilica@[SFDAIL] in the next runs. GRAPHICAL ABSTRACT?: SYNOPSIS Two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles via hydrogen bonding. The catalytic activity of the catalysts was investigated in the synthesis of diesters under solvent-free conditions.
- Fareghi-Alamdari, Reza,Niri, Mehri Nadiri,Hazarkhani, Hassan
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- Synthesis of monoesters and diesters using eco-friendly solid acid catalysts - Cerium(IV) and thorium(IV) phosphates
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In the present endeavour, amorphous cerium phosphate (CP) and thorium phosphate (TP) have been synthesized by sol-gel method and also under microwave irradiation to yield CPM and TPM. CP, TP, CPM and TPM have been characterized for elemental analysis (ICP-AES), spectral analysis (FTIR), thermal analysis (TGA), X-ray diffraction studies, SEM, EDX, surface area (BET) and surface acidity (NH3-TPD). The potential use of these materials as solid acid catalysts has been explored by studying esterification as a model reaction. Monoesters such as ethyl acetate (EA), propyl acetate (PA), butyl acetate (BA), benzyl acetate (BzAc) and diesters such as diethyl malonate (DEM), diethyl succinate (DES), dibutyl phthalate (DBP), dioctyl phthalate (DOP) have been synthesized. Esterification conditions have been optimized by varying several parameters such as reaction time, catalyst amount and mole ratio of reagents. The catalytic activity has been compared and correlated with reference to surface acidity of the catalysts. It is found that catalytic activity of CPM > CP > TP M > TP. The regenerated catalysts could be reused upto two catalytic runs without significant loss in % yields of esters formed. The highlighting feature of the present work is the catalysts CPM and TPM that are synthesized in a much shorter reaction time with higher surface acidity giving good % yield of esters.
- Parangi, Tarun,Wani, Bina,Chudasama, Uma
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p. 430 - 438
(2013/09/23)
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- Structural characterisation of degradation products formed upon di-n-butyl phthalate radiolysis by high-performance liquid chromatography electrospray tandem mass spectrometry
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Structural characterisation of 15 degradation products, formed upon di-n-butyl phthalate (DBP) radiolysis, has been achieved using a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) coupling. The dissociation behaviour of protonated DBP was first established to be further used to characterise structural deviation in the degradation products. Based on accurate mass measurements, compounds shown by HPLC-MS analysis were all found to be DBP oxidation products, amongst which various sets of isomers could be distinguished. Collision-induced dissociation experiments performed on each electrosprayed molecule first allowed unambiguous definition of the location of the additional oxygen atoms; that is, in the alkyl branch or on the aromatic ring. Although location of the oxygen atom in the alkyl branches could not always be precisely determined, relative abundances of some product ions allowed oxygenated functions to be identified.
- Tintaru, Aura,Labed, Veronique,Charles, Laurence
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experimental part
p. 595 - 603
(2011/11/12)
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- Ring-opening of cyclic anhydrides using ionic liquids
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Four novel Bronsted acidic ionic liquids with two different acid sites on the imidazolium cations were synthesised and employed as catalysts and solvents for the ring-opening of cyclic anhydrides to synthesise half-esters. The results showed that these novel Bronsted acidic ionic liquids were efficient and recyclable. Good yields, short reaction times and mild reaction conditions were achieved.
- Jiang, Dong,Wang, Yuan Yuan,Xu, Yan Nan,Dai, Li Yi
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experimental part
p. 167 - 169
(2009/10/15)
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- Use of zirconium(IV) phosphate as a solid acid catalyst in some esterification reactions
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Amorphous and crystalline phases of zirconium(IV) phosphate of the class of tetravalent metal acid (TMA) salts have been synthesized by sol-gel method. The materials have been characterized for elemental analysis (ICP-AES), thermal analysis (TGA), X-ray analysis, BET surface area, surface acidity (NH 3-TPD) and FTIR spectroscopy. Chemical resistivity of the materials has been accessed in acids, bases and organic solvent media. The exchangeable protons present in the structural hydroxyl groups indicate good potential for TMA salts to be investigated as solid acids. Esterification reaction has been selected as a model reaction to study the application of ZrP (amorphous and crystalline phases) as a solid acid. The catalytic activity explored by synthesizing monoesters and diesters reveals the promising use of ZrP as an ecofriendly solid acid catalyst.
- Patel,Joshi,Chudasama
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p. 348 - 352
(2008/09/19)
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- Revised structure for spatozoate, a metabolite of Spatoglossum variabile
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Structure of spatozoate, n-butyl 2-benzoyloxymethylbenzoate 1, a metabolite of Spatoglossum variabile has been revised into benzyl n-butyl phthalate 2 by synthesis. NMR spectral data of synthetic 2 agrees well with those reported for the natural spatozoate.
- Cheng, Kur-Ta,Rajasekhar, Dodda,Huang, Sheng-Tung,Hsu, Feng-Lin,Subbaraju, Gottumukkala V.
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p. 1190 - 1192
(2007/10/03)
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- Monitoring of phthalic acid monoesters in river water by solid-phase extraction and GC-MS determination
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An analytical method for monitoring 10 phthalic acid monoesters in river water was investigated by solid-phase extraction, methylation with diazomethane, and GC-MS. Two cartridge-type solid phases packed with octadesyl-coated silica (C18) and styrenedivinyl polymer (PS-2) and one disk-type solid phase made from octadesyl-coated styrene-divinylbenzene polymer (SDB-XD) were investigated in solid-phase extraction. PS-2 gave the highest recoveries of the three solid phases, and recoveries of more than 80% of the monoesters in filtered water samples were obtained at pH 2 to 3 with PS-2 at the spiked level of 0.1 μg L-1, except for monomethyl-phthalate (MMP), in which more than 72% of the monoesters were recovered. For the monoesters in the suspended solids (SS), an acidic methanol extract of SS was added to purified water acidified to pH 2, and the monoesters were extracted with PS-2. The recoveries of the monoesters in SS were more than 80%, but the recoveries of MMP were more than 57%. The method detection limit (MDL) of each phthalic acid monoester in 500 mL of water sample and in 2 mg of dry weight of SS ranged from 0.010 to 0.030 μg L-1 and from 1 to 11 μg g-1 respectively. Monitoring of phthalic acid monoesters in the Tama River in Tokyo was conducted every month from March 1999 to February 2000 using the present method. MMP, mono-n-butyl-phthalate (MBP), and mono-(2-ethylhexyl)-phthalate (MEHP) were detected at concentrations of 0.030-0.0340, 0.010-0.480, and 0.010-1.30 μg L-1. respectively, in the filtered water samples but were not detected in SS. Dimethyl-phthalate (DMP), di-n-butyl-phthalate (DBP), and di-(2-ethylhexyl)-phthalate (DEHP) were detected in the river water at concentrations of 0.010-0.092, 0.008-0.540, and 0.013-3.60 μg L-1, respectively. Diethyl-, di-iso-butyl-, and benzylbutyl-phthalates were also detected at concentrations of nanograms per liter, whereas the corresponding monoesters did not appear. The concentrations of MBP and MEHP in the river water were slightly lower than those of the corresponding diesters at the majority of sampling sites and sampling times.
- Suzuki,Yaguchi,Suzuki,Suga
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p. 3757 - 3763
(2007/10/03)
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- Amine Catalyzed Intramolecular Imidization of Alkyl and Aryl Phthalamates. Kinetics and Mechanism in Deuteriated Chloroform
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The kinetics of the amine catalyzed intramolecular imidization of the alkyl and phenyl phthalamates with a variety of amines were measured in deuteriated chloroform at 40.1 deg C.An overall second-order kinetic rate law, rate = koverall, was obtained from our experiments.Although pre-association between the amides and the amines through hydrogen bonding interaction was suggested by proton NMR spectroscopy, the catalytic ability of amines was found to be related to their basicity rather than to their hydrogen bonding ability or nucleophilicity.This observation implies the involvement of proton transfer from the amide to the amine in the critical transition state.In addition, by changing the leaving group from phenoxy to butoxy group, the reaction rate constants decrease by a factor of 30 to 70.On the basis of these kinetic results, we propose that the intramolecular imidization proceeds through an amine assisted cyclization to a zwitterionic intermediate, followed by the expulsion of the alkoxy or phenoxy group to provide phthalimide and the corresponding alcohol.
- Leung, Man-kit,Frechet, Jean M. J.
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p. 2329 - 2336
(2007/10/02)
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- NOUVEAUX DECONTAMINANTS. ACTION DES PERACIDES A GROUPE ESTER SUR QUELQUES TOXIQUES INSECTICIDES OU DE GUERRE
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A new peroxyacid-ester series has been obtained and used in the destruction of toxic agents.These structures oROCOC6H4CO3H and ROCO(CH2)nCO3H are more stable than the unsubstituted compounds.The reaction with paraoxon (O,O-diethyl O-paranitrophenylphosphate) and HD (2,2'-dichlorodiethylsulfide) goes to completion in a very short time.The influence of the R group and the length of the chain (n=2......12) has been studied.The addition of some long chain tetraalkyl-ammonium salts enhances the rate of the reaction by micellar catalysis.
- Lion, C.,Hedayatullah, M.,Bauer, P.,Boukou-Poba, J. P.,Charvy, C.,et al.
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p. 555 - 560
(2007/10/02)
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