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Search for "hydrolysis" in Full Text gives 889 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Polymer and small molecule mechanochemistry: closer than ever

  • José G. Hernández

Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128

Graphical Abstract
  • cellulose and chitin and approximation to the structure of lignin. Tensile forces by ball milling change the conformation of a chitin model compound. This deformation facilitates the subsequent cleavage of glycosidic bonds to produce oxocarbenium ion intermediates for hydrolysis [45]. (a) Representation of
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Published 14 Sep 2022

Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide

  • Blaine G. Fiss,
  • Georgia Douglas,
  • Michael Ferguson,
  • Jorge Becerra,
  • Jesus Valdez,
  • Trong-On Do,
  • Tomislav Friščić and
  • Audrey Moores

Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125

Graphical Abstract
  • following milling and aging, can also have occurred. Additionally, the phosphorus 2p signal in g-h-PCN showed the majority of phosphorus exists as a mixture of P=O and P–O species, with a major peak centered at 133.6 eV (69%, Figure 2c). These species are formed by oxidation with air and hydrolysis upon
  • =O character from 21% to 18% compared to g-h-PCN and an increase in C–OH character from 35% to 43% suggests mild hydrolysis, likely of terminal trichloroheptazine, during the annealing step at 300 °C, even under a flow of argon gas (Figure 2d). The nitrogen 1s scans show a similar trend, with the
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Letter
Published 12 Sep 2022

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

  • Dmitry Dar’in,
  • Grigory Kantin,
  • Alexander Bunev and
  • Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

Graphical Abstract
  • 16 was obtained and its structure was confirmed by single-crystal X-ray analysis. Presumably, the formation of ester 16 can be justified by the trapping of the carbocation intermediate 17 (vide infra) by the formamide carbonyl oxygen atom followed by hydrolysis of the iminium moiety (Scheme 4
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Published 22 Aug 2022

New azodyrecins identified by a genome mining-directed reactivity-based screening

  • Atina Rizkiya Choirunnisa,
  • Kuga Arima,
  • Yo Abe,
  • Noritaka Kagaya,
  • Kei Kudo,
  • Hikaru Suenaga,
  • Junko Hashimoto,
  • Manabu Fujie,
  • Noriyuki Satoh,
  • Kazuo Shin-ya,
  • Kenichi Matsuda and
  • Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2022, 18, 1017–1025, doi:10.3762/bjoc.18.102

Graphical Abstract
  • N2H4, which could be generated upon the acid hydrolysis of azoxy natural products. In the assay, N2H4 is captured by two equivalents of p-dimethylaminobenzaldehyde (DAB) to generate p-dimethylaminobenzaldazine, which can be sensitively detected by HPLC by monitoring the UV absorption at 485 nm (Scheme
  •  1). As a result, we observed the generation of N2H4 upon the hydrolysis of solid-culture extracts of both Streptomyces strains (Supporting Information File 1, Figure S1). Therefore, we attempted to isolate the azoxy natural products in an N2H4-detecting assay guided manner. The extracts of
  • Streptomyces sp. RM72 were first partitioned by water and ethyl acetate, and then the organic layer was further fractionated by silica gel column chromatography. Fractionation by reversed-phase HPLC yielded ten compounds (1–10) that generate N2H4 upon acid hydrolysis. The combination of 1H and 13C NMR with a
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Published 10 Aug 2022

On Reuben G. Jones synthesis of 2-hydroxypyrazines

  • Pierre Legrand and
  • Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 935–943, doi:10.3762/bjoc.18.93

Graphical Abstract
  • would be the hydrolysis of the α-aminoamides and the resulting α-amino acids would also be water-soluble. For these reasons, a low temperature as well as a plausibly softer base (i.e., tetraalkylammonium hydroxides) would be key parameters to alleviate the impact of these side reactions. These would
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Published 29 Jul 2022

Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides

  • Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 889–915, doi:10.3762/bjoc.18.90

Graphical Abstract
  • % yield via the acid-catalyzed addition to the cyano group and subsequent cyclocondensation, hydrolysis, and tautomerization. Alternatively, the reaction of (E)-2-cyano-N'-((4-oxo-4H-chromen-3-yl)methylene)acetohydrazide (220) and phosphorus tribromide in the presence of triethylamine in dioxane followed
  • by two step hydrolysis gave the same product 223 in 28% yield. Phosphorus tribromide first reacted with more nucleophilic amide nitrogen atom to form dibromophosphanamine derivative 224 by loss of HBr. The more nucleophilic dibromophosphanamine derivative 224 further underwent a nucleophilic addition
  • to the cyano group followed by hydrolysis to give the final product 223 (Scheme 36). The product 223 showed antitumor activity in a biological assay [20]. To develop antioxidants and antitumor agents, the same group synthesized chromene-fused 5-oxo-1,2-azaphospholidine 2-oxide derivatives. The
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Published 22 Jul 2022

Synthesis and HDAC inhibitory activity of pyrimidine-based hydroxamic acids

  • Virginija Jakubkiene,
  • Gabrielius Ernis Valiulis,
  • Markus Schweipert,
  • Asta Zubriene,
  • Daumantas Matulis,
  • Franz-Josef Meyer-Almes and
  • Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 837–844, doi:10.3762/bjoc.18.84

Graphical Abstract
  • gave the corresponding (2-substituted pyrimidin-4-yloxy)acetates 6–9. In order to replace the 2-methylsulfonyl group with a hydroxy group, we tested several techniques. It was found that heating compound 5 with water in dimethyl sulfoxide at 100 °C or boiling for 1 h in water led to hydrolysis of both
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Published 13 Jul 2022

Synthesis of α-(perfluoroalkylsulfonyl)propiophenones: a new set of reagents for the light-mediated perfluoroalkylation of aromatics

  • Durbis J. Castillo-Pazos,
  • Juan D. Lasso and
  • Chao-Jun Li

Beilstein J. Org. Chem. 2022, 18, 788–795, doi:10.3762/bjoc.18.79

Graphical Abstract
  • byproduct was fully characterized by NMR, and the structure was confirmed by SCXRD, we conceived a hydrolysis protocol to break apart the formed enol ether (fully described in section 2.4 of Supporting Information File 1). After brief optimization, we succeeded at recovering the portion of
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Published 04 Jul 2022

An isoxazole strategy for the synthesis of 4-oxo-1,4-dihydropyridine-3-carboxylates

  • Timur O. Zanakhov,
  • Ekaterina E. Galenko,
  • Mikhail S. Novikov and
  • Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2022, 18, 738–745, doi:10.3762/bjoc.18.74

Graphical Abstract
  • cyanation of the resulted isoxazoles 8a–f to cyanides 9a–f using Me2C(OH)CN/(Me2N)2C=NH [29], their acid hydrolysis, followed by esterification of the resulting acids 9a–f with diazomethane. 4-Iodoisoxazoles 12a–f, necessary for the preparation of 3,4-disubstituted isoxazoles, were obtained by iodination of
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Published 23 Jun 2022

A trustworthy mechanochemical route to isocyanides

  • Francesco Basoccu,
  • Federico Cuccu,
  • Federico Casti,
  • Rita Mocci,
  • Claudia Fattuoni and
  • Andrea Porcheddu

Beilstein J. Org. Chem. 2022, 18, 732–737, doi:10.3762/bjoc.18.73

Graphical Abstract
  • after 1h (70%, GC–MS analysis). Reducing the amount of sodium carbonate did not provide any advantage. Interestingly, using anhydrous sodium carbonate instead of its hydrated form improved reaction yields, likely due to the hydrolysis of tosyl chloride. With these data in hand, we then opted for
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Published 22 Jun 2022

Terpenoids from Glechoma hederacea var. longituba and their biological activities

  • Dong Hyun Kim,
  • Song Lim Ham,
  • Zahra Khan,
  • Sun Yeou Kim,
  • Sang Un Choi,
  • Chung Sub Kim and
  • Kang Ro Lee

Beilstein J. Org. Chem. 2022, 18, 555–566, doi:10.3762/bjoc.18.58

Graphical Abstract
  • compounds (1–5) were isolated and characterized from G. hederacea var. longituba (Figure 1). Structures of these compounds were established by 1D and 2D NMR and HRESIMS, comparison of experimental and calculated ECD data, DP4+ analysis, and hydrolysis. Herein, the isolation and structural elucidation of the
  • spectrum of 1S,4S,5R,8S,10R-(1a). Finally, the ᴅ-glucopyranosyl moiety was identified by GC–MS analysis of a chiral derivatization product of the sugar obtained by enzyme hydrolysis of 1 [9][10]. The retention time of glucopyranose (11.3 min) corresponded to that of the standard ᴅ-glucopyranose (11.3 min
  •  3C). The experimental ECD spectrum of 2 showed a negative Cotton effect at 233 nm and positive Cotton effects at 217 and 257 nm, which showed a similarity with those of calculated ECD spectrum of 1R,4R,5S,6S,8S,10S-(ent-2a). Enzyme hydrolysis and following sugar identification were performed using
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Published 17 May 2022

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

  • Man-Ping Li,
  • Nan Yang and
  • Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

Graphical Abstract
  • synthesized starting from the known TBTQ-based hexakis(propargyl ether) 1 [29] (Scheme 1a). Through the CuAAC reaction with ethyl azidoacetate under Cu(I) catalysis, the TBTQ-based hexakis(ethyl acetate) compound 2 was obtained in 73% yield. Subsequent hydrolysis with sodium hydroxide followed by
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Published 12 May 2022

The asymmetric Henry reaction as synthetic tool for the preparation of the drugs linezolid and rivaroxaban

  • Martin Vrbický,
  • Karel Macek,
  • Jaroslav Pochobradský,
  • Jan Svoboda,
  • Miloš Sedlák and
  • Pavel Drabina

Beilstein J. Org. Chem. 2022, 18, 438–445, doi:10.3762/bjoc.18.46

Graphical Abstract
  • modified synthetic procedure [14]. Here, it was included the chromatographic purification of the final chloroformates, which led to removing of corresponding alkyl chlorides formed as byproducts. The aldehyde 17 was prepared by a different way, because the acid-catalyzed hydrolysis of its acetal
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Published 14 Apr 2022

Menadione: a platform and a target to valuable compounds synthesis

  • Acácio S. de Souza,
  • Ruan Carlos B. Ribeiro,
  • Dora C. S. Costa,
  • Fernanda P. Pauli,
  • David R. Pinho,
  • Matheus G. de Moraes,
  • Fernando de C. da Silva,
  • Luana da S. M. Forezi and
  • Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

Graphical Abstract
  • electrophilic bromination of the corresponding phenol, followed by hydrolysis promoted by H2O2 [66]. Variations in the methods of 2-methylnaphthol (17) oxidation to menadione (10) with H2O2 were made by changing the catalytic systems in order to increase the yield and selectivity. These include the catalysis by
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Published 11 Apr 2022

Amamistatins isolated from Nocardia altamirensis

  • Till Steinmetz,
  • Wolf Hiller and
  • Markus Nett

Beilstein J. Org. Chem. 2022, 18, 360–367, doi:10.3762/bjoc.18.40

Graphical Abstract
  • form a salimethyloxazolinyl-thioester intermediate, which then undergoes a C–N bond opening resulting in an ester formation. Eventually, the thioester undergoes a hydrolysis reaction leading to compound 6. The compounds, which were discovered in this study, are members of the large family of nocobactin
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Published 30 Mar 2022

Site-selective reactions mediated by molecular containers

  • Rui Wang and
  • Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

Graphical Abstract
  • , azides, halides and alkenes, oxidation of remote C–H bonds and alkenes, and substitution reactions involving ring-opening cyclization of epoxides, nucleophilic substitution of allylic chlorides, and hydrolysis reactions. The product selectivity is interpreted as the consequence of the space shape and
  • ester group in turn to the aqueous solution. Addition of base would result in the hydrolysis of one ester group to the corresponding carboxylic acid. Product distributions indicated a two- to four-fold relative decrease in the hydrolysis rate constant of the second ester caused by the confined space in
  • the cavitand, which enhanced the selectivity of the monoester product 45. Similarly, the monohydrolysis of α,ω-diisocyanate 46 was achieved using the water-soluble cavitand D (Figure 13b) [77]. The residual isocyanate group was buried deep in the cavity of D and protected from further hydrolysis. The
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Published 14 Mar 2022

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

  • Marco Manenti,
  • Leonardo Lo Presti,
  • Giorgio Molteni and
  • Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

Graphical Abstract
  • described by Ellman and co-workers, but the expected α-aminoboronate could not be isolated. Extensive hydrolysis of the starting ketimine occurred, allowing only the recovery of the 1-methyl-isatin precursor. In the light of this initial outcome, we started a detailed screening of reaction conditions (Table
  • of water to the minimum necessary to solubilize the copper sulfate. Thus, performing the reaction in toluene/water 100:1, ketimine hydrolysis was almost entirely prevented and the yield of compound 2a raised to 52% (Table 1, entry 6). With regard to the ligand (Table 1, entries 7 and 8), PPh3 behaved
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Published 10 Mar 2022

Glycosylated coumarins, flavonoids, lignans and phenylpropanoids from Wikstroemia nutans and their biological activities

  • Meifang Wu,
  • Xiangdong Su,
  • Yichuang Wu,
  • Yuanjing Luo,
  • Ying Guo and
  • Yongbo Xue

Beilstein J. Org. Chem. 2022, 18, 200–207, doi:10.3762/bjoc.18.23

Graphical Abstract
  • by a ROESY correlation between H-6'' and H-1'''. Subsequently, an acid hydrolysis of 1 afforded the products including daphnogitin, a ᴅ-glucose, and a ᴅ-xylose. The absolute configurations of glucopyranosyl and xylopyranosyl was further determined by HPLC analysis of the sugar derivatives (Supporting
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Published 16 Feb 2022

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

  • Irina Kuznetcova,
  • Felix Bacher,
  • Daniel Vegh,
  • Hsiang-Yu Chuang and
  • Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

Graphical Abstract
  • further reacted with potassium cyanide to yield nitrile 12 [27]. Saponification of the nitrile was performed by exploiting the Pinner reaction with saturated HCl gas in methanol. This led to methyl indol-2-ylacetate (13) in 83% yield [28]. The hydrolysis of ester 13 was performed in the presence of
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Published 26 Jan 2022

Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides

  • Malcolm J. D’Souza and
  • Dennis N. Kevill

Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13

Graphical Abstract
  • , in water as solvent, both electron-supplying and electron-withdrawing substituents decreased the rate of the hydrolysis of benzenesulfonyl chloride. They proposed, consistent with the claim by Hall [12], that with electron-supplying substituents the reaction proceeded, in part, by an ionization (SN1
  • of hydrolysis measured in aqueous dioxane [22]. The observations concerning the specific rates were consistent with an SN2 pathway for the displacement of the chloride ion from the sulfur. However, for the trisubstituted 2,4,6-trimethylbenzenesulfonyl chloride, the SN2 mechanism does not give a
  • simple rationale for the high specific rate of solvolysis observed and a partial changeover to an SN1 pathway was proposed. Vizgert [14][15] had previously suggested that the favored pathway for the hydrolysis of this substrate was by an SN1 ionization mechanism [25]. This proposal was based on the lack
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Published 17 Jan 2022

Efficient and regioselective synthesis of dihydroxy-substituted 2-aminocyclooctane-1-carboxylic acid and its bicyclic derivatives

  • İlknur Polat,
  • Selçuk Eşsiz,
  • Uğur Bozkaya and
  • Emine Salamci

Beilstein J. Org. Chem. 2022, 18, 77–85, doi:10.3762/bjoc.18.7

Graphical Abstract
  • H-7 and H-10 also showed weak correlation, which clearly supports the cis relation of the proton H-10. In this reaction, lactonization and hydrolysis of the Boc group to the corresponding amine were observed. The formation of lactone 8 as the major product can be explained by nucleophilic attack of
  • the neighbouring carboxyl group, which was formed by hydrolysis of the corresponding methyl ester. For the synthesis of other isomeric β-amino acid derivatives, epoxide 7 was treated with two equivalent amounts of NaHSO4 [27] in methylene chloride/MeOH at room temperature (Scheme 3). The formation of
  • . Synthesis of cyclic β-amino acid 6. Epoxidation of Boc-protected amino ester 4 and hydrolysis of epoxide 7 with HCl(g)–MeOH. Reaction of epoxide 7 with NaHSO4 in methylene chloride/MeOH. Synthesis of cyclic β-amino acid derivative 8. Suggested mechanism for the reaction of epoxide 7 with NaHSO4. Supporting
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Published 06 Jan 2022

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

  • Ruan Carlos B. Ribeiro,
  • Patricia G. Ferreira,
  • Amanda de A. Borges,
  • Luana da S. M. Forezi,
  • Fernando de Carvalho da Silva and
  • Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

Graphical Abstract
  • isomerization involves two routes: one through the hydrolysis of 22 leading to lawsone (4) and the subsequent addition of arylamines in position C2, and the other involves the addition of arylamines at position C2 of 22, leading to 24 with two equivalents of arylamine, which after hydrolysis of the imine at
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Published 05 Jan 2022

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

  • Hendrik Gruß,
  • Rebecca C. Feiner,
  • Ridhiwan Mseya,
  • David C. Schröder,
  • Michał Jewgiński,
  • Kristian M. Müller,
  • Rafał Latajka,
  • Antoine Marion and
  • Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

Graphical Abstract
  • data [72]. Moreover, the epimerization by the conditions of SMC is unlikely as it has been excluded by total hydrolysis of a late-stage SMC modified RGD peptide [67]. Analysis of the secondary structures of the cyclic peptides P2–P4 by CD spectroscopy also did not show a significantly increased α
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Published 03 Jan 2022

A photochemical C=C cleavage process: toward access to backbone N-formyl peptides

  • Haopei Wang and
  • Zachary T. Ball

Beilstein J. Org. Chem. 2021, 17, 2932–2938, doi:10.3762/bjoc.17.202

Graphical Abstract
  • . C–O cleavage, Figure 1A) through H-atom abstraction from a photoexcited intermediate, which produces an oxonium-type intermediate (in brackets). Hydrolysis of this intermediate then affords an alcohol product. Recently [16][17], we demonstrated that vinylogous analogues of this mechanism (Figure 1B
  • -formyl product iii, a possible intermediate on the path to product i via imide hydrolysis. To better understand the mechanism of photocleavage and the appearance of the formyl product iii, we first identified the 2-nitroaryl-derived byproducts produced in this reaction. Model compound 1 was subjected to
  • nitroso 3, and related compounds 4 and 5 are all consistent with the classical C–X cleavage mechanism and with hydrolysis of the presumed oxonium intermediate 6’, but are inconsistent with the production of formyl products. In contrast, photoirradiation of the same alkenyl ether 6 under acidic conditions
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Published 15 Dec 2021

A two-phase bromination process using tetraalkylammonium hydroxide for the practical synthesis of α-bromolactones from lactones

  • Yuki Yamamoto,
  • Akihiro Tabuchi,
  • Kazumi Hosono,
  • Takanori Ochi,
  • Kento Yamazaki,
  • Shintaro Kodama,
  • Akihiro Nomoto and
  • Akiya Ogawa

Beilstein J. Org. Chem. 2021, 17, 2906–2914, doi:10.3762/bjoc.17.198

Graphical Abstract
  • –Volhard–Zelinsky-type ring-opening reaction of 1a (Table 1). In this reaction, the corresponding acid bromide is formed in situ by heating with Br2 and a substoichiometric amount of PBr3; the acid bromide is then converted into 2,5-dibromopentanoic acid (2a) via hydrolysis during the workup under open-air
  • . Lactone 1a (5 mmol) was allowed to react with Br2 (2.0 equiv) and PBr3 (5 mol %) at 80 °C for 24 h, with subsequent hydrolysis successfully affording in 2a in 90% yield (Table 1, entry 1). In the absence of a substoichiometric amount of PBr3, the transformation of 1a to 2a hardly proceeded (Table 1, entry
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Published 09 Dec 2021
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