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Articles de revues sur le sujet « Acetyl »

Auteur : Grafiati
Publié le 4 juin 2021
Mis à jour le 27 avril 2022

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1

Sastre, Juan A. López, José Molina Molina, Dolores Portal Olea et Cristina Romero-Avila. « A new synthesis of 2,5-anhydro-D-mannose derivatives ». Canadian Journal of Chemistry 66, no 12 (1 décembre 1988) : 2975–80. http://dx.doi.org/10.1139/v88-462.

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Penta-O-acetyl-D-glucose diethyl dithioacetal monoxide 3 was obtained by oxidation of penta-O-acetyl-D-glucose diethyl dithioacetal 2 with 3-chloroperbenzoic acid. By reaction of 3 with sodium methoxide in methanol and further acetylation, 3,4,6-tri-O-acetyl-2,5-anhydro-D-mannose-diethyl dithioacetal monoxide 8 and the reduction product 3,4,6-tri-O-acetyl-2,5-anhydro-1,1-bis(ethylthio)-1-deoxy-D-arabino-hex-1-enitol 4 were obtained. Reduction of 8 yielded the corresponding dithioacetal derivative 9, which was converted to 3,4,6-tri-O-acetyl-2,5-anhydro-D-mannose diethyl acetal 11.
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2

Pan, Xuejun, Neil Gilkes et Jack N. Saddler. « Effect of acetyl groups on enzymatic hydrolysis of cellulosic substrates ». Holzforschung 60, no 4 (1 juillet 2006) : 398–401. http://dx.doi.org/10.1515/hf.2006.062.

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Abstract Evidence showed that acetyl groups introduced during acetic acid delignification was a primary cause of the poor enzymatic digestibility of acetic acid pulp. The inhibition by acetyl groups could be removed by saponification. Acetyl groups might inhibit the enzymes by interfering with the productive binding (hydrogen bonds) between cellulose and the catalytic domain of cellulases, by affecting the binding of CBD to cellulose, or by increasing the diameter of the cellulose chain.
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3

Hadzic, Pavle, Nada Vukojevic, Mirjana Popsavin et Janos Canadi. « Nucleophilic opening of the 3,5-anhydro ring in 1,2-O-cyclohexylidene- -D-xylofuranose ». Journal of the Serbian Chemical Society 66, no 1 (2001) : 1–8. http://dx.doi.org/10.2298/jsc0101001h.

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The reactivity of the oxetane ring in 3,5-anhydro-1,2-O-cyclohexylidene- -D-xylofuranose (1) was exemplified by its regiospecific nucleophilic opening. The action of concentrated hydrobromic or hydroiodic acid on 1 resulted in the exclusive formation of the 5-deoxy-5-halo derivatives, while the action of acetyl chloride or acetyl bromide yielded the corresponding 3-O-acetyl-5-deoxy-5-halo derivatives in 70 - 90 % yield. Under strongly acidic reaction conditions, the protection of the cyclohexylidene acetal function remained intact.
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4

Hanaya, Tadashi, Kiyoshi Torigoe, Kazuyuki Soranaka, Horoshi Yamamoto, Yao Qizhengt et Wolfgang Pfleiderer. « Pteridines CV ». Pteridines 6, no 1 (février 1995) : 1–7. http://dx.doi.org/10.1515/pteridines.1995.6.1.1.

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Summary Treatment of L-biopterin (I) with N,N-dimethyformamide dimethyl- (or diethyl)acetal and then with acetic anhydride in pyridine gave 1',2'-di-O-acetyl-N'-(N,N-dimethylaminomethylene)-L-biopterin (4), which was converted by the Mitsunobu reaction into 3-methyl (5) and 3-p-nitrophenetyl derivatives (7). The protective groups on the side chain diols and N2 of these compounds were selectively cleaved to furnish products 6, 8-10, among which 9 is naturally occurring 3-methyl-L-biopterin and 8 is N',N(3)-protected biopterin, a versatile intermediate for various reactions on the side-chain diol. In contrast, the same Mitsunobu reactions of tri-N2:I',2'-0-acetyl-L-biopterin (II) afforded 04-methyl (12) and 04-NPE derivatives (13), both of which yielded 0 4-methyl-L-biopterin (14) and subsequently led to 4-amino-L-biopterin (18).
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5

Kantlehner, Willi, Birgit Heckel et Jochen Mezger. « Orthoamide und Iminiumsalze, CI. Umsetzungen von N,N,N′,N′-Tetramethylharnstoffdiethylacetal mit CH2-aciden Verbindungen ». Zeitschrift für Naturforschung B 75, no 9-10 (26 novembre 2020) : 865–80. http://dx.doi.org/10.1515/znb-2020-0072.

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AbstractN,N,N′,N′-Tetramethylurea diethylacetal reacts with CH2-acidic compounds as benzylcyanide, cyanoacetic acid derivatives malonodinitrile and nitromethane to give ketene aminals or ketene-O,N-acetales. Low polar solvents favour mostly the formation of ketenaminals. The yields of ketenaminals and ketene-O,N-acetals can be improved in some cases by addition of trimethylsilyldimethylamine. The reactions of the urea acetal with diethylmalonate, ore acetyl acetone, stops at the stage of the N,N′,N″-permethylated guanidinium salts with carbanionic counterions. The formation of bis(dimethylamino)methylene-diethylmalonate from the urea acetal and diethylmalonate can be initiated by addition of trimethylsilyldimethylamine/trimethylsilylcyanide. N,N,N′,N′,N″,N″-Hexamethylguanidinium cyanide is formed in the analogous reactions of the urea acetal with N,N-dimethylcyanacetamide or diethylsuccinate. The N,N′,N″-Hexamethyl-guanidinium nitrite can be obtained from the urea acetal and nitropropane.
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6

Phalke, Pallavi L. « Synthesis of different α, β- unsaturated oxazolone derivatives ». Journal of Drug Delivery and Therapeutics 9, no 1 (15 janvier 2019) : 124–27. http://dx.doi.org/10.22270/jddt.v9i1.2189.

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Acetyl glycine were prepared from glycine acetic anhydride and then 2, 4-disubstituted Oxazol-5-one were prepared from acetyl glycine, substituted aldehydes, acetic anhydride, and sodium acetate as a catalyst. The formed product is evaluated and characterized by thin layer chromatography, infrared spectroscopy and melting point. The, β- unsaturated shows ability to react with various nucleophilic reagents for synthesis of new fused oxazole compounds. Keywords: glycine, acetic anhydride, aldehyde Sodium acetate, Oxazolone, E. coli, Antibacterial Activity.
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7

Rosenqvist, Marie. « Acetyl Group Distribution in Acetylated Wood Investigated by Microautoradiography ». Holzforschung 55, no 3 (25 avril 2001) : 270–75. http://dx.doi.org/10.1515/hf.2001.045.

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Summary Sapwood of Scots pine (Pinus silvestris L.) was acetylated with 14C- and 3H-labelled acetic anhydride. The distribution of acetyl groups was investigated with microautoradiography and microautoradiographs were evaluated with ESEM, Environmental Scanning Electron Microscopy. The investigation showed that the impregnation of wood with radioisotope-labelled substances provides a good opportunity to investigate the location of substances covalently bonded to the wood material. Introduced 14C-labelled acetyl groups show an even distribution in the wood cell wall, with no discernible concentration gradients at acetylation levels of about 5, 15 and 20% weight gain. 3H-labelled acetyl groups show an even distribution in the wood cell wall at 15 and 20% weight gain, with no discernible concentration gradients. At the 5% weight gain level, however, an uneven distribution of 3H-labelled acetyl groups over the cell wall is observed. Nevertheless, the unevenness is random and no concentration gradient is discernible at this level. 3H with a relatively high resolution, 0.5–1 μm, compared to 14C with a resolution of 2–5 μm, gives more accurate information about where exactly the acetyl groups are situated in the wood cell wall. Acetic anhydride was evenly distributed when a full impregnation procedure was used. The chemical and physical properties of acetic anhydride allow a uniform penetration into the pine cell wall and a complete acetylation takes place when the specimens are heated.
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8

Sekar, M., S. Vanitha et K. J. Rajendra Prasad. « Synthesis of Novel 3-Acetyl-2-hydroxy-1-N,N-diacetylaminocarbazole Derivatives ». Zeitschrift für Naturforschung B 49, no 5 (1 mai 1994) : 687–90. http://dx.doi.org/10.1515/znb-1994-0521.

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Abstract The synthesis of hitherto unknown 3-acetyl-2-hydroxy-1-N,N-diacetylaminocarbazole (3a-f), is reported. The hydroxyiminocarbazoles (2a-f), prepared from 1-oxo-1,2,3,4-tetra-hydrocarbazoles (1a -f) on treatment with acetyl chloride in acetic anhydride yielded the title compounds (3a-f).
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9

Chênevert, Robert, Michel Desjardins et René Gagnon. « Enzyme Catalyzed Asymmetric Hydrolysis of Chloral Acetyl Methyl Acetal ». Chemistry Letters 19, no 1 (janvier 1990) : 33–34. http://dx.doi.org/10.1246/cl.1990.33.

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10

Patil, Ravikant, Joseph Genco, Hemant Pendse et Adriaan Van Heiningen. « Process for producing acetic acid in hardwood kraft pulp mills ». May 2017 16, no 05 (2017) : 287–300. http://dx.doi.org/10.32964/tj16.5.287.

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To determine the economic feasibility of producing acetic acid from commercial hardwood chips in kraft pulp mills, laboratory experiments were conducted to obtain sufficient data to perform a preliminary economic analysis for a proposed acetic acid recovery process. The acetyl groups in northeast hardwood were hydrolyzed from the xylan polymers in the wood to obtain sodium acetate. The extraction experiments were performed by using 4%–6% sodium hydroxide at low temperature (50°C–80°C). Sodium acetate from the extract was concentrated and then converted into acetic acid and sodium hydroxide by salt splitting using bipolar membrane electrodialysis (BPMED). Flow diagrams were prepared and cost estimates made for the capital and operating costs for the proposed acetic acid recovery process. The discounted cash flow rate of return on investment was estimated for pulp mills in the range of 1000–2000 tons/day. A preliminary economic analysis showed that the discounted cash flow rate of return on investment is primarily a function of (1) the plant size, (2) the selling price of acetic acid, and (3) the content of acetyl groups present in wood species. The income for the process and thus the rate of return on investment increases with increasing acetyl content in the wood and selling price of the acetic acid. When food grade acetic acid is produced, for example, the rate of return varies between 9% and 16% depending upon the size of the pulp mill, assuming the wood contains 3.5% acetyl groups on a dry basis and the selling price of acetic acid is US$900/ton.
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11

Journal, Baghdad Science. « Synthesis and characterization of some heterocyclic including oxazoles,Thiazoles, Pyridazines, phthalizines and Pyrazoles with evaluating of biological activity. » Baghdad Science Journal 10, no 3 (1 septembre 2013) : 818–27. http://dx.doi.org/10.21123/bsj.10.3.818-827.

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A series of new compounds including p-bromo methyl pheno acetate [2]. N-( aminocarbonyl)–p-bromo pheno acetamide [3] , N-( aminothioyl) -p-bromo phenoacetyl amide [4], N-[4-(p-di phenyl)-1,3-oxazol-2-yl]-p-bromopheno acetamide [5],N-[4-p-di phenyl]-1,3-thiazol-2-yl-p-bromo phenoacet amide [6], p-bromopheno acetic acid hydrazide [7] , 1-N-(p-bromo pheno acetyl)-1,2-dihydro-pyridazin-3,6- dione [8], 1-N-(p-bromo pheno acetyl)-1,2-dihydro-phthalazin-3,8- dione[ 9], 1-(p-bromo pheno acetyl)-3-methylpyrazol-5-one [10] and 1-(p-bromo phenol acetyl)- 3,5-dimethyl pyrazole [11] have been synthesized. The prepared compounds were characterized by m.p.,FT-IR and 1H-NMR spectroscopy. Also ,the biological activity was evaluated .
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12

MARSDEN, F. « Acetyl Cellulose ». Journal of the Society of Dyers and Colourists 21, no 4 (22 octobre 2008) : 102–8. http://dx.doi.org/10.1111/j.1478-4408.1905.tb00329.x.

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13

Kishimoto, T., H. Tsuji, Y. Uraki et Y. Sano. « Ozone Bleaching of Atmospheric Acetic Acid Hardwood Pulp from Betula platyphylla var. japonica Hara ». Holzforschung 57, no 2 (27 février 2003) : 181–88. http://dx.doi.org/10.1515/hf.2003.027.

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Summary Atmospheric acetic acid pulp from Japanese white birch was bleached with 1–5% ozone with and without intermediate mild alkaline extraction. Concentrated acetic acid was a more effective bleaching media than water. Mild alkaline extraction of ozone-prebleached pulp was found to be very effective in delignification of the pulp and did not have any undesirable effects on pulp properties. A sufficiently delignified acetic acid pulp was obtained with multi-stage ozone bleaching in Z1Z2Z3 or Z1EZ2EZ3 bleaching sequence with a total ozone consumption of 2.17% on oven-dry pulp. The pulp from a Z1EZ2EZ3 sequence still contained 3.51% acetyl groups, which was 75% of the original amount of acetyl groups in unbleached acetic acid pulp.
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14

Morzycki, Jacek W., Zenon Łotowski, Monika Stȩpniowska, Agnieszka Gryszkiewicz et Agnieszka Z. Wilczewska. « Nitration of N-acetyl enamines with acetyl nitrate ». Tetrahedron 53, no 47 (novembre 1997) : 16161–68. http://dx.doi.org/10.1016/s0040-4020(97)10074-6.

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15

Tobin Kåhrström, Christina. « Acetyl phosphate revealed as a global acetyl donor ». Nature Reviews Microbiology 11, no 9 (16 août 2013) : 597. http://dx.doi.org/10.1038/nrmicro3100.

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16

Lakhmanov, D. E., Yu G. Khabarov, V. A. Veshnyakov et M. R. Yokubjanov. « Nitration of Hydrolysis Lignin in Water-Aprotic Solvent Mixtures ». Lesnoy Zhurnal (Forestry Journal), no 5 (5 novembre 2020) : 184–92. http://dx.doi.org/10.37482/0536-1036-2020-5-184-192.

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Industrial lignins are formed from native lignins during chemical or biochemical processing of plant raw materials. Lignins can be modified to produce valuable products, including monomers, polymeric materials, and composites. The article presents the results of a study of hydrolysis lignin nitration under various conditions. The aim of the study was to obtain a nitrated hydrolysis lignin with a maximum yield and maximum nitrogen content. Therefore, the nitration was carried out using nitric acid in a water-aprotic solvent binary mixtures (1,4-dioxane, dimethyl sulfoxide, tetrahydrofuran, dimethylformamide, acetonitrile). Acetyl nitrate, which is a mixed anhydride of nitric and acetic acids, was also used as a nitrating agent. In this regard, the consumption of acetic anhydride in the synthesis of acetyl nitrate was used taking into account the water present in concentrated nitric acid. Acetyl nitrate was obtained by the reaction of acetic anhydride and concentrated nitric acid at room temperature for 30 min. Acetyl nitrate is a mild nitrating agent opposed to nitric acid. Nitration was carried out under reflux in a boiling water bath for 2–5 min (with nitric acid) or 1–60 min (with acetyl nitrate). Upon completion of the nitration reaction, the products were filtered, washed with distilled water and dried to constant weight without heating. When nitration was performed with nitric acid, the maximum yield of nitrated hydrolysis lignin (83–101 %) was achieved using 1,4-dioxane, acetonitrile, and tetrahydrofuran; and the maximum nitrogen content (4.3–4.5 %) was achieved using 1,4-dioxane or acetonitrile. The use of dimethyl sulfoxide and dimethylformamide leads to a decrease in the product yield to 23–35 %, to a lower nitrogen content of 1.3–3.9 % and an increased oxygen content, which indicates the occurrence of not only nitration, but also depolymerization and oxidative transformations. When nitration with acetyl nitrate, the reaction takes place for 1–3 min, herewith the product contains up to 4.7 % of nitrogen. On the IR spectra of nitrated hydrolysis lignins, new absorption bands appear at 1555 and 1710 cm–1 due to the appearance of carboxyl and nitro groups.
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17

Ke, Wei Chang, Yi Kun Chen, Guo Xi Xiong, Xiang Hong Peng, Chao Zhu et Xiao Qiu Yang. « Synthesis and Characterization of the Water-Soluble Oleoyl Acetyl Chitosan ». Advanced Materials Research 284-286 (juillet 2011) : 1782–85. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1782.

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Oleoyl chloride was synthesized by oleic acid and thionyl dichloride (SOCl2), and then reacted with chitosan in dichloromethane to obtain the oleoyl chitosan. Novel water-soluble oleoyl acetyl chitosan (OACh) was synthesized using oleoyl chloride reacted with acetic anhydride in pyridine. The chemical structure of the OACh was characterized by FT-IR, 1H and 13C NMR. There existed the peaks at 1743.9 cm-1 (C=O) and 1658.1 cm-1(C=C) in FT-IR spectrum, and the peaks at 170.8, 171.6 and 172.5 ppm which were assigned to the C=O of the oleoyl and acetyl groups in 13C NMR spectrum. The results indicated that OACh had oleoyl as hydrophobic moieties and acetyl as hydrophilic moieties.
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18

Yi, Y., H. Gholami, M. G. Morrow et B. Borhan. « XtalFluor-E® mediated proto-functionalization of N-vinyl amides : access to N-acetyl N,O-acetals ». Organic & ; Biomolecular Chemistry 15, no 45 (2017) : 9570–74. http://dx.doi.org/10.1039/c7ob02283b.

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19

Wibisana, Ahmad, Dewi Nurul Aulia, Siti Nurhidayah, Dewi Hisi Anggaraeni et Fischar Chicko. « Karakteristik Pati Talas Banten yang Dimodifikasi Menggunakan Asetat Anhidrida ». Jurnal Ilmiah Teknik Kimia 6, no 1 (31 janvier 2022) : 33. http://dx.doi.org/10.32493/jitk.v6i1.15549.

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Taro beneng (Xanthosoma undipes k.koch) is a tuber plant originating from Pandeglang. Taro tubers have a high starch content so they are the potential to be used in various industrial applications such as in the fields of food, textiles, paper, and others. In general, the use of natural starch for the industry has disadvantages related to its Physico-chemical characteristics. For a wider application, starch needs to be modified in order to have certain characteristics that are suitable for a certain application. In this study, a starch modification was carried out by the acetylation method using acetic anhydride. The independent variables used in this study were the ratio of acetic anhydride/dry starch (g/g): 0, 5, 10, 20%, while the dependent variables were % acetyl, degree of acetylation, swelling power, and solubility. The acetylation reaction was carried out at 35°C for 30 minutes. The results showed that starch acetylation using an acetic anhydride/starch ratio of 10 g/50 g resulted in percent acetylation (% acetyl) and degree of substitution (DS) were 4.3% and 0.16%, respectively. The highest swelling power value was 5.2 g/g, while the highest acetyl starch solubility was 1.6% which was obtained on acetylation using an acetic anhydride/starch ratio of 5/50 g/g.
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20

Chang, Cindy, Ku Chiao Chu et Stephen Yue. « Anhydrous Deprotection of Dimethyl Acetals with Acetyl Chloride/ZnCl2 ». Synthetic Communications 22, no 8 (avril 1992) : 1217–20. http://dx.doi.org/10.1080/00397919208021108.

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21

Puliti, Raffaella, et Carlo Andrea Mattia. « AmmoniumN-acetyl-L-threoninate and methylammoniumN-acetyl-L-threoninate ». Acta Crystallographica Section C Crystal Structure Communications 56, no 4 (15 avril 2000) : 496–99. http://dx.doi.org/10.1107/s0108270100001268.

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22

Edwards, Oliver E., Dusan Dvornik, Ralph J. Kolt et Barbara A. Blackwell. « Formation, reactions, and NMR spectra of 1,20-cycloatidanes ». Canadian Journal of Chemistry 70, no 5 (1 mai 1992) : 1397–405. http://dx.doi.org/10.1139/v92-178.

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Imines derived from the alkaloid atisine gave N-acetyl 1,20-cycloatidane derivatives when heated with acetic anhydride. Vigorous alkaline hydrolysis cleaved the cyclopropane ring, regenerating the parent imine. The 1H and 13C NMR spectra of several 1,20-cyclo derivatives have been assigned and compared to those of the parent imines 2. All of the N-acetyl compounds showed doubling of the majority of the NMR resonances, due to amide rotamers. The effects of the cyclopropane ring current are noted.
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23

You, Yanzhi, Shujuan Yang, Lingxi Bu, Jianxin Jiang et Dafeng Sun. « Comparative study of simultaneous saccharification and fermentation byproducts from sugarcane bagasse using steam explosion, alkaline hydrogen peroxide and organosolv pretreatments ». RSC Advances 6, no 17 (2016) : 13723–29. http://dx.doi.org/10.1039/c5ra26356e.

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24

Tang, Ai Min, et Kai Wang. « Study on Esterification Characteristics of TEMPO-Oxidized Cellulose ». Advanced Materials Research 749 (août 2013) : 49–53. http://dx.doi.org/10.4028/www.scientific.net/amr.749.49.

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Oxidized cellulose acetate (OCA) with carboxylic acid group on C-6 position of glucose is a kind of biodegradable functional materials which can be dissolved in organic solvents. First, cellulose was oxidized with TEMPO (2, 2, 6, 6-tetramethyl-piperidyl-1-oxyl) oxidation system, and then OCA was produced via esterification by reacting the oxidized cellulose with acetic anhydride. The influence factors such as carboxylic content of oxidized cellulose, reaction temperature, reaction time, and concentration of acetic anhydride on degree of substitution (DS) of acetyl group and intrinsic viscosity ([η]) of OCA were investigated. The result revealed that the DS of acetyl group can be increased effectively from 2.61 to 2.74 by increasing reaction temperature from 50°C to 80°C, and from 2.58 to 2.72 by prolonging reaction time from 40min to 180min, but the [η] of the product decreased at the same time. An increase in concentration of acetic anhydride led to an increase in DS and [η] of OCA. As the carboxyl content increased from 0.383 mmol/g to 0.797 mmol/g, the DS of acetyl group decreased from 2.81 to 2.73. That result revealed the carboxyl content also has a great influence on the esterification characteristics.
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25

Graikou, Konstantia, Nektarios Aligiannis, Ioanna B. Chinou et Catherine Harvala. « Cantleyoside-dimethyl-acetal and Other Iridoid Glucosides from Pterocephalus perennis – Antimicrobial Activities ». Zeitschrift für Naturforschung C 57, no 1-2 (1 février 2002) : 95–99. http://dx.doi.org/10.1515/znc-2002-1-217.

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Cantleyoside-dimethyl-acetal (6), was isolated from the endemic Greek plant Pterocephalus perennis subsp. perennis in addition to five other known iridoid glucosides, loganin, loganic acid, cantleyoside, secologanin, and secologanin-dimethyl-acetal. The structure of these compounds was determined by all spectroscopic means mainly by NMR and MS techniques. The above compounds as well as their acetyl derivatives were tested against six Gram positive and negative bacteria and three pathogenic fungi.
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26

Vila, Carlos, Gil Garrote, Herminia Domínguez et Juan Carlos Parajó. « Hydrolytic Processing of Rice Husks in Aqueous Media : A Kinetic Assessment ». Collection of Czechoslovak Chemical Communications 67, no 4 (2002) : 509–30. http://dx.doi.org/10.1135/cccc20020509.

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The kinetics of hemicellulose decomposition in the non-isothermal rice husk autohydrolysis was experimentally assessed. Experimental data on the time course of the concentrations of hemicellulosic polymers (xylan, araban and acetyl groups) and their autohydrolysis products (including sugar oligomers, monosaccharides, furfural and acetic acid) were fitted to several kinetic models based on multiple pseudohomogeneous first-order reactions. Sugar oligomers were the major reaction products. The hydrolytic conversion of xylan, araban and acetyl groups was well interpreted by kinetic models based on consecutive and parallel reactions.
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27

Al-Saleh, Balkis, Nouria Al-Awadi, Halema Al-kandari, Mervat Mohammed Abdel-Khalik et Mohamed Hilmy Elnagdi. « Studies with 2H pyranones : Synthesis of new 3-substituted-4-hydroxy-2H-pyran-2-ones ». Journal of Chemical Research 2000, no 1 (janvier 2000) : 16–17. http://dx.doi.org/10.3184/030823400103165725.

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3-Acetyl-4-hydroxy-6-methyl-2H-pyran-2-one 1a condensed with N,N-dimethylformamide dimethyl acetal yielding the enaminone 3a. The latter reacted with a variety of reagents affording pyridine derivatives 11, benzofuranoylpyranes 14 and 17, pyranylpyranes 22, pyranylpyrazole 29a,b and pyranylisoxazole 33.
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Whitlock, Barbara J., et Howard W. Whitlock. « Intracavity acetyl transfer ». Tetrahedron Letters 29, no 47 (1988) : 6047–50. http://dx.doi.org/10.1016/s0040-4039(00)82261-3.

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Hart, Andrew M., Andrew DH Wilson, Cristina Montovani, Colette Smith, Margaret Johnson, Giorgio Terenghi et Mike Youle. « Acetyl-l-carnitine ». AIDS 18, no 11 (juillet 2004) : 1549–60. http://dx.doi.org/10.1097/01.aids.0000131354.14408.fb.

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30

John, E., J. A. Potenza et H. J. Schugar. « Acetyl benzyl disulfide ». Acta Crystallographica Section C Crystal Structure Communications 44, no 2 (15 février 1988) : 390–91. http://dx.doi.org/10.1107/s0108270187010217.

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Schroeder, Sabrina, Tobias Pendl, Andreas Zimmermann, Tobias Eisenberg, Didac Carmona-Gutierrez, Christoph Ruckenstuhl, Guillermo Mariño et al. « Acetyl-coenzyme A ». Autophagy 10, no 7 (15 mai 2014) : 1335–37. http://dx.doi.org/10.4161/auto.28919.

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Cashman, Timothy J., et Chinmay M. Trivedi. « N-Acetyl Transferases ». Circulation Research 128, no 8 (16 avril 2021) : 1170–72. http://dx.doi.org/10.1161/circresaha.121.319049.

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Ibrahim, Hassan K., Sayed H. El-Tamany, Reda F. El-Shaarawy et Ibrahim M. El-Deen. « Synthesis and investigation of mass spectra of some novel benzimidazole derivatives ». Macedonian Journal of Chemistry and Chemical Engineering 27, no 1 (15 juin 2008) : 65. http://dx.doi.org/10.20450/mjcce.2008.248.

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2-Substituted benzimidazoles (3) and (4a-c) were prepared via condensation of ethyl 2-thionyl-pyruvate (1) and hydrazidoyl derivatives (2a-c) with o-phenylene diamine in acetic acid. Acetylation of compound (4a) with acetic anhydride yielded the corresponding N-acetyl derivative (5). Treatment of compound 4b with hydrazine hydrate gave the corresponding hydrazino derivative (6). Reaction of 2-[(2-thionyl)acetyl)] benzimidazole (3) with hydrazine hydrate gave the pyrazolyl derivative (7) and hydrazino derivative (8). Alkylation of compound 3 with alkyl halide gave the corresponding 2,3-disubstituled benzimidazoles (9a, b). Pyrrolo[1,2-a] benzimidazole derivatives 10 and 11 were prepared via cyclocondensation of compound 3 with acetic anhydride in presence of AcONa and phosphorus oxychloride. The electron impact mass spectra of both of the above series of compounds have also been recorded and their fragmentation patterns are discussed.
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Fujino, Takahiro, Yukio Ikeda, Timothy Osborne, Sadao Takahashi, Tokuo Yamamoto et Juro Sakai. « Sources of Acetyl-CoA : Acetyl-CoA Synthetase 1 and 2 ». Current Medicinal Chemistry-Immunology, Endocrine & ; Metabolic Agents 3, no 3 (1 septembre 2003) : 207–10. http://dx.doi.org/10.2174/1568013033483375.

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MORZYCKI, J. W., Z. LOTOWSKI, M. STEPNIOWSKA, A. GRYSZKIEWICZ et A. Z. WILCZEWSKA. « ChemInform Abstract : Nitration of N-Acetyl Enamines with Acetyl Nitrate. » ChemInform 29, no 9 (23 juin 2010) : no. http://dx.doi.org/10.1002/chin.199809187.

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King, Russell R., et Larry A. Calhoun. « Synthesis and NMR characteristics of N -acetyl-4-nitro, N -acetyl-5-nitro, N -acetyl-6-nitro and N -acetyl-7-nitrotryptophan methyl esters ». Magnetic Resonance in Chemistry 47, no 3 (28 novembre 2008) : 273–76. http://dx.doi.org/10.1002/mrc.2377.

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Salman, Ghazwan Ali. « Synthesis of Novel 3-Acetyl N-methyl-2- Quinolone Derivatives with Expected Antimicrobial Activity ». Al-Mustansiriyah Journal of Science 28, no 2 (11 avril 2018) : 73. http://dx.doi.org/10.23851/mjs.v28i2.502.

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A series of new 3-Acetyl N-Methyl-2-quinolones oxadiazoles derivatives were synthesized by reaction of 3-acetyl-4-hydroxy-1-methylquinolin-2(1H)-one 3 with ethylbromoacetate to produce compounds 4. The hydrazinolysis of compound 4 with hydrazine hydrate afforded hydrazide compounds 5. New Schiff bases 6 were obtained by condensation of compound 5 with different aryl aldehydes. The last step involves refluxing compound 6 with acetic anhydrides to give the corresponding 3-acetyl-N-methylquinolin-2-one oxadiazoles 7. All the synthesized compounds were characterized on the basis of FT-IR, 1H-NMR and 13C-NMR. The synthesized compounds have been evaluated for antimicrobial activity against Gram-positive and Gram-negative bacteria. Among sixteen synthesized novel compounds, in which five compounds (7a, 7b, 7c, 7e, 7g) ex-hibited promising Antimicrobial activity as compared to Trimethoprim (100μg/ml).
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Polnaya, Febby J., Hilda Hilda et Cynthia G. C. Lopulalan. « KONSENTRASI ASAM ASETAT MEMENGARUHI KARAKTERISTIK FISIKOKIMIA PATI SAGU IHUR TERASETILASI ». Jurnal Teknologi dan Industri Pangan 31, no 2 (décembre 2020) : 180–87. http://dx.doi.org/10.6066/jtip.2020.31.2.180.

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Native ihur sago starch is a starch from Maluku and to date there is no report on its physicochemical properties. The objective of this work was to evaluate the effect of acetic acid concentration on the physicochemical properties of the native ihur sago starch. The starch was acetylated at different acetic acid concentrations, i.e., 0, 0.5, 1.5, and 2.5%. The acetylation was carried out by reacting ihur sago starch solution (100 g in 225 mL water) with acetic acid under alkaline condition. The acetyl group, degree of substitution (DS), water solubility, swelling power, paste clarity, and water, ash and amylose contents of the acetylated starch were measured. The study was conducted in three replications of non-factorial experiments using a completely randomized design. Starch modification through acetic acid addition produced ihur sago starch with different physicochemical characteristics from that of its native form. The acetylation caused the hydroxyl group in the starch to be substituted by acetyl group at concentration of 1.336-1.850% and DS range of 0.026-0.046, whilst no acetyl group was detected in its native starch. Acetylation increased the starch ash content from 0.46% to 0.50-0.57%, amylose content from 28.86% to 29.73-31.46%, solubility from 12.83% to 14.20-25.20%, swelling power from 18.51 g/g to 16.74-28.24 g/g and paste clarity from 93.07%T650 to 93.50-94.13%T650. In addition, acetylation at 0.5% increased the water content of the starch while higher concentration of acetylation could decrease its water content.
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Chen, Raymond, Sonja Sekulic et Todd Zelesky. « Development and Validation of a Cost-Effective, Efficient, and Robust Liquid Chromatographic Method for the Simultaneous Determination of the Acetyl and Succinoyl Content in Hydroxypropyl Methylcellulose Acetate Succinate Polymer ». Journal of AOAC INTERNATIONAL 85, no 4 (1 juillet 2002) : 824–31. http://dx.doi.org/10.1093/jaoac/85.4.824.

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Abstract A reversed-phase liquid chromatographic method was developed and validated for the determination of the content of free acetic acid, free succinic acid, acetyl substituents, and succinoyl substituents in hydroxypropyl methylcellulose acetate succinate (HPMCAS; Chemical Abstracts Service Registry No. 71138-97-1) polymer. This single new method gave accurate and precise measurement of both acetyl and succinoyl substituents, which had previously required 3 Japanese Pharmaceutical Excipients (JPE) methods to accomplish. Consequently, analysis time and turnaround time are decreased significantly. Furthermore, this method can also separate and determine the free acetic and succinic acids in HPMCAS polymer, a task that the corresponding JPE method cannot achieve. The values for accuracy (average recovery from 12 standard samples) were 99.9% for acetic acid and 99.8% for succinic acid. The values for injection precision (relative standard deviation [RSD]) were 0.11% for acetic acid and 0.28% for succinic acid. The values for intermediate precision (RSD) were 1.25% for determination of the acetyl content at the 8.78% (w/w) level and 1.33% for determination of the succinoyl content at the 10.9% (w/w) level. The values for intermediate precision (RSD) were 5.98% for determination of free acetic acid at the 0.12% (w/w) level and 5.13% for determination of free succinic acid at the 0.029% (w/w) level. The method was proven to be robust with respect to variation in the pH of the mobile phase, the concentration of potassium dihydrogen phosphate, and the flow rate. The method is well suited for quality control in today's fast-paced pharmaceutical laboratories.
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Adams, An, et Norbert De Kimpe. « Chemistry of 2-Acetyl-1-pyrroline, 6-Acetyl-1,2,3,4-tetrahydropyridine, 2-Acetyl-2-thiazoline, and 5-Acetyl-2,3-dihydro-4H-thiazine : Extraordinary Maillard Flavor Compounds ». Chemical Reviews 106, no 6 (juin 2006) : 2299–319. http://dx.doi.org/10.1021/cr040097y.

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Al-Salman, Sattar Jabbar Ahmed. « Evaluation of Antibacterial and Cytoxicity Activities of 5-Nitro Acetyl Salicylic Acid and 5-Bromo Acetyl Salicylic Acid Compounds ». Journal of Medical Science And clinical Research, no 03 (29 mars 2017) : 19578–83. http://dx.doi.org/10.18535/jmscr/v5i3.196.

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Cambie, RC, DS Larsen, CEF Rickard, PS Rutledge et PD Woodgate. « Experiments Directed Towards the Synthesis of Anthracyclinones. X. A Synthesis of (±)-4-Demethoxydaunomycinone ». Australian Journal of Chemistry 39, no 3 (1986) : 487. http://dx.doi.org/10.1071/ch9860487.

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The acetal methyl 2-(3-dimethoxymethyl-4-hydroxy-1-methoxy-9,10-dioxo- 9,10-dihydroanthracen-2-yl)acetate (2), a versatile intermediate prepared earlier from quinizarin (1), has been converted into (�)-4- demethoxydaunomycinone (5) in 43% yield (on a small scale) from the acetal (2) and in 29% overall yield from quinizarin. The structure of (�)-9α-acetyl-6,9-dihydroxy-7α,11-dimethoxy-5,7,8,9,10,12-hexahydronaphthacene-5,12-dione (6), an intermediate in the sequence, has been confirmed by X-ray studies.
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43

Roth, Andreas, et Hans Faillard. « Synthesis of Fluorescent 7,8,9-Tri-O-acetyl-N-acetyl- and 4-O-Acetyl-N-acetylneuraminic Acid α-Thioketosides ». Liebigs Annalen der Chemie 1993, no 5 (12 mai 1993) : 485–89. http://dx.doi.org/10.1002/jlac.199319930180.

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Koll, P., et J. Kopf. « Crystal and Molecular Structures of Penta-O-acetyl-aldehydo-D-glucose Dimethyl Acetal and of Hepta-O-acetyl-aldehydo-D-glucose Hydrate ». Australian Journal of Chemistry 49, no 3 (1996) : 391. http://dx.doi.org/10.1071/ch9960391.

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The solid-state structures of the title compounds were determined by conventional single-crystal X-ray crystallography. In both cases a planar zigzag conformation of the carbon skeleton is observed with a resulting 1,3-parallel orientation of O(2) and O(4). In the case of the heptaacetate even a second such arrangement is established between O(3) and one of the oxygens at C(1). These findings substantiate the claim that such conformations are not as unfavourable as previously was assumed by many authors.
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Dzvinchuk, Igor B., Sergey A. Kartashov, Myron O. Lozinskii, Eduard B. Rusanov et Alexander N. Chernega. « Formation of 1,3,4-Oxadiazoles by Cyclisation of Acetoacetanilide Acylhydrazones under Mild Conditions ». Journal of Chemical Research 2002, no 2 (février 2002) : 82–83. http://dx.doi.org/10.3184/030823402103171221.

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Selective and efficient cyclisation of acetoacetanilide acylhydrazones into previously inaccessible 3-acetyl-2-anilinocarbonylmethyl-2,3-dihydro-2-methyl-1,3,4-oxadiazoles was achieved in acetic anhydride by use of acid catalysis at 40–50°C.
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46

Geary, Gemma C., Eric G. Hope, Kuldip Singh et Alison M. Stuart. « Preparation of iodonium ylides : probing the fluorination of 1,3-dicarbonyl compounds with a fluoroiodane ». RSC Advances 5, no 21 (2015) : 16501–6. http://dx.doi.org/10.1039/c4ra15733h.

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The isolated iodonium ylide has been reacted successfully with TREAT-HF, hydrochloric acid, acetic acid and p-toluenesulfonic acid to form the 2-fluoro-, 2-chloro-, 2-acetyl- and 2-tosyl-1,3-ketoesters respectively.
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Lamba, Doriano, Cenydd Burden, William Mackie et Bernard Sheldrick. « The crystal and molecular structure of hexa-O-acetyl-carrabiose dimethyl acetal ». Carbohydrate Research 155 (novembre 1986) : 11–17. http://dx.doi.org/10.1016/s0008-6215(00)90129-0.

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Jesús Diánez, M., M. D. Estrada, A. López-Castro et S. Pérez-Garrido. « N-Acetyl-2,3,4,6-tetra-O-acetyl-N-benzyl-β-D-glucopyranosylamine ». Acta Crystallographica Section C Crystal Structure Communications 53, no 3 (15 mars 1997) : 378–79. http://dx.doi.org/10.1107/s0108270196014230.

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Dalbouha, Samira, et María L. Senent. « Large amplitude vibrations of acetyl isocyanate, methyl cyanoformate, and acetyl cyanate ». Physical Chemistry Chemical Physics 21, no 7 (2019) : 3597–605. http://dx.doi.org/10.1039/c8cp04490b.

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The far infrared region of three detectable molecules sharing the empirical formula C3H3O2N, acetyl isocyanate CH3CONCO (AISO), methyl cyanoformate NC–COOCH3 (MCN) and acetyl cyanate CH3COOCN (ACN), is explored using explicitly correlated coupled cluster ab initio methods and a variational procedure designed for non-rigid species and large amplitude motions.
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Sumathi, R., et Minh Tho Nguyen. « Theoretical Study on Unimolecular Reactions of Acetyl Cyanide and Acetyl Isocyanide ». Journal of Physical Chemistry A 102, no 2 (janvier 1998) : 412–21. http://dx.doi.org/10.1021/jp9724582.

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