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DMAP-Catalyzed [4+2] Cycloaddition of α,β-Unsaturated Carboxylic Acids with Ketones for Synthesis of ,β-Unsaturated δ-Lactones (pages 397–400) 被引量:1
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作者 Jinghai Jin Qinchang Xu Weiping Deng 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第4期397-400,共4页
The DMAP-catalyzed [4+2] cycloaddition of α,β-unsaturated carboxylic acids with ketones furnishing α,β-unsaturated δ-lactones in good yields (up to 80%) is described, which is the first example of remote -C(s... The DMAP-catalyzed [4+2] cycloaddition of α,β-unsaturated carboxylic acids with ketones furnishing α,β-unsaturated δ-lactones in good yields (up to 80%) is described, which is the first example of remote -C(sp^3)-H activation of α,β-unsaturated carboxylic acids facilitated by DMAP, a pyridine-based catalyst. 展开更多
关键词 DMAP CYCLOADDITION α β-unsaturated carboxylic acids α β-unsaturated δ-lactones
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Copper-Catalyzed C-C(O)C Bond Cleavage of Monoalkylated β-Diketone: Synthesis of α,β-Unsaturated Ketones
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作者 Tony Wheellyam Pouambeka Victor N’goka +3 位作者 Narcisse Nicaise Obaya Guy Crépin Enoua Hubert Makomo Qian Zhan 《International Journal of Organic Chemistry》 2023年第2期41-49,共9页
A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition m... A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition metal in a weakly basic medium (K<sub>3</sub>PO<sub>4</sub>) at room temperature. To carry out this study, we first had to synthesize the monoalkylated β-diketones 1. Afterwards, α,β-unsaturated ketones 2 were obtained with high yields around 80%. Finally, all the products were characterized by 1H NMR, 13C NMR, and HRMS spectra. . 展开更多
关键词 Monoalkylated β-diketone α β-unsaturated Ketones COPPER-CATALYZED C-C(O)C Bond Cleavage
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Corrosion inhibition of α,β-unsaturated carbonyl compounds on steel in acid medium 被引量:5
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作者 Gao Jiancun Weng Yongji +2 位作者 Salitanate Feng Li Yue Hong 《Petroleum Science》 SCIE CAS CSCD 2009年第2期201-207,共7页
Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that... Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that both cinnamaldehyde and benzalacetone had an evident anticorrosion effect and could reduce the corrosion of steel effectively in acid medium, α,β-unsaturated carbonyl compounds with a benzene ring structure had good adsorption on steel surface. The experiments proved that polymerization of α,β-unsaturated carbonyl compounds on the steel surface at a high temperature and in concentrated acid medium resulted in a good corrosion inhibiting effect, which was attributed to the structures of α,β-unsaturated carbonyl compounds. 展开更多
关键词 α β-unsaturated carbonyl compounds corrosion inhibitor ADSORPTION oilfield acidizing treatment
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Gallium trichloride-catalyzed conjugate addition of indole and pyrrole to α,β-unsaturated ketones in aqueous media 被引量:5
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作者 Rong Xu Jin Chang Ding +2 位作者 Xi An Chen Miao Chang Liu Hua Yue Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第6期676-679,共4页
Michael addition of indole and pyrrole to a variety of α, β-unsaturated ketones was efficiently promoted by a catalytic amount of GaCl3 in aqueous media to afford the corresponding products in good to excellent yields.
关键词 Gallium trichloride Michael addition INDOLE PYRROLE α β-unsaturated ketones
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Stereoselective Addition of Organotitanium and Grignard Reagents to 3,5-O-isopropylidene-L-glucurono-γ-lactone 被引量:5
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作者 Hong CHEN Shao Yi SUN and De Quan YU(Institute of Meteria Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第10期889-892,共4页
Substituted PhMgX and PhTi(OCHMe2)4MgX react with 3,5-O-isopropylidene-L-glucurono-γ-lactone 4 to give tetrads 5a-e and its stereoisomers 6a-e Tetrads 5a-e are the important intermediates in the synthesis of howiinol... Substituted PhMgX and PhTi(OCHMe2)4MgX react with 3,5-O-isopropylidene-L-glucurono-γ-lactone 4 to give tetrads 5a-e and its stereoisomers 6a-e Tetrads 5a-e are the important intermediates in the synthesis of howiinol Al and its derivatives. The stereoselectivities of substituted PhTi(OCHMe2)4Mg (5a-e:6a-e ratio, 68-72:32-28) were better than those of substituted PhMgX(33-64:67-36) in the reaction. The effects of different substitUted groups and positions (p-Me, m-Me, o-MeO, p-Cl) of the phenyl ring on their stereoselectivies were not significant. 展开更多
关键词 Organotitanium reagents Stereoselective reaction 3 5-O-isopropylidene-L-glucurono-γ-lactone
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Synthesis of α,β-Unsaturated Ketones using Potassium fluoridealumina Catalyst by Microwave Irradiation 被引量:4
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作者 Xiao Hui ZHANG Da Bin GAO +1 位作者 Ming GUO Shan Zhen YAN(Department of Chendstry and Chemical Engineering, Dalian University, Dalian 116622) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第6期521-522,共2页
Microwave irradiation can accelerate the rate of the synthetic reaction of α,β-unsaturated ketones by using KF-Al2O3 as catalyst. The rate enhancement of the reaction is 360-860 fold.
关键词 Microwave irradiation α β-unsaturated ketone KF-Al_2O_3
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Two new α,β-unsaturated butyrolactone derivatives from Pleione bulbocodioides 被引量:2
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作者 Xin Qiao Liu Wen Yuan Gao +2 位作者 Yuan Qiang Guo Tie Jun Zhang Lu Lu Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1075-1077,共3页
Two new α,β-unsaturated butyrolactone derivatives, 4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one (1) and 3-(3′-hydroxyphenethyl)furan-2(5H)-one (2), together with one known phenolic compound (3), w... Two new α,β-unsaturated butyrolactone derivatives, 4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one (1) and 3-(3′-hydroxyphenethyl)furan-2(5H)-one (2), together with one known phenolic compound (3), were isolated from the tubers of Pleione bulbocodioides (Franch.) Rolfe. Their structures were elucidated by analysis of spectroscopic data. 展开更多
关键词 Pleione bulbocodioides α β-unsaturated butyrolactone Phenolic compound
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cDNA Fragment Cloning of L-Galactono-1,4-Lactone Dehydrogenase andIt's Expression in Different Organs of R. roxburghii Tratt 被引量:3
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作者 ANHua-ming CHENLi-geng FANWei-guo 《Agricultural Sciences in China》 CAS CSCD 2004年第11期807-811,共5页
A 855 bp cDNA encoding L-galactono-1,4-lactone dehydrogenase (GalLDH) fragment was cloned from fruit of R. roxburghii Tratt by the method of RT-PCR, on the basis of the homologous genes of Arabidopsis thaliana, caul... A 855 bp cDNA encoding L-galactono-1,4-lactone dehydrogenase (GalLDH) fragment was cloned from fruit of R. roxburghii Tratt by the method of RT-PCR, on the basis of the homologous genes of Arabidopsis thaliana, cauliflower, sweet potato, strawberry, etc. in GenBank. Sequence analysis showed 79-92% identity in nucleotide sequence and 75-87% identity in amino acid sequence to that of strawberry and Arabidopsis thaliana, etc. Northern blot showed that the expression of GalLDH was significantly different in different organs. The transcription level of GalLDH in fruit was significantly higher than that in leaf, stem and root respectively. Furthermore, this expression mode was highly correlated with AsA levels. 展开更多
关键词 R. roxburghii Tratt L-galactono-1 4-lactone dehydrogenase (GalLDH) Ascorbic acid (AsA) Gene expression
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Methanol as hydrogen source: Chemoselective transfer hydrogenation of α,β-unsaturated ketones with a rhodacycle 被引量:1
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作者 Ahmed H. Aboo Robina Begum +2 位作者 Liangliang Zhao Zahoor H. Farooqi Jianliang Xiao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第11期1795-1799,共5页
Methanol is a safe, economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes high... Methanol is a safe, economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes highly chemoselective hydrogenation of α,β-unsaturated ketones with methanol as the hydrogen source. A wide variety of chalcones, styryl methyl ketones and vinyl methyl ketones, including sterically demanding ones, were reduced to the saturated ketones in refluxing methanol in a short reaction time, with no need for inter gas protection, and no reduction of the carbonyl moieties was observed. The catalysis described provides a practically easy and operationally safe method for the reduction of olefinic bonds in α,β-unsaturated ketone compounds. 展开更多
关键词 α β-unsaturated ketones Transfer hydrogenation METHANOL Rhodium complex CHEMOSELECTIVITY
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Chemoselective synthesis of δ-lactones via benzyl radical cyclization utilizing K_2S_2O_8-CuCl_2 被引量:1
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作者 N.O.Mahmoodi K.Tabatabaeian +1 位作者 M.Kosari S.Zarrabi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第12期1431-1434,共4页
Direct chemoselective oxidation of δ-lactones via highly stable benzyl radical cyclization is reported. The one-pot conversion of premade substituted 5-aryl pentanoic acid and 8-benzyl-1-naphthoic acid in the presenc... Direct chemoselective oxidation of δ-lactones via highly stable benzyl radical cyclization is reported. The one-pot conversion of premade substituted 5-aryl pentanoic acid and 8-benzyl-1-naphthoic acid in the presence of K2S2Os--CuCl2 results to the δ-lactones in moderate to good yields. The advantages of this methodology is using water as a solvent and utilizing available starting materials. 展开更多
关键词 δ-lactones Benzyl radical Chemoselective oxidation K2S2O8-CuCl2
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Nickel (Ⅱ) Complex Catalyzed Conjugate Addition Reaction of Functionalised Organozinc Reagents to α,β -Unsaturated Esters 被引量:1
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作者 Yu Lai HU Jian Hua YU +2 位作者 Shi Yan YANG Yuan Qi YIN Jin Xian WANG(State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics. Chinese Academy of Sciences, Lanzhou 730000)(Department of Chemistry, Northwest Normal U 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期17-18,共2页
Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in... Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in excellent yields. 展开更多
关键词 Conjugate addition reaction organozinc reagents α β-unsaturated esters nickel complex CATALYSIS
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Chemoselective Catalytic Hydrogenation of α,β-Unsaturated Ketones and α,β-Unsaturated Carboxylic Esters
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作者 ZHANG Jing-wen ZHAO Jian-zhang +6 位作者 ZHANG Xiao-long JIANG Yu-lin MA Xiu-li SUN Yun-xiu JIANG Wen-pu LI Yao-xian XU Zhi-luo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第2期17-22,共6页
The effect of catalysts P-2 00-Ni(Nickel boride) and P-2 00-Ni-M(M: Co, Fe, Cu, Sn), prepared by adopting a modified recipe, on the chemoselective hydrogenation of carbon carbon double bonds in α,β- unsaturated... The effect of catalysts P-2 00-Ni(Nickel boride) and P-2 00-Ni-M(M: Co, Fe, Cu, Sn), prepared by adopting a modified recipe, on the chemoselective hydrogenation of carbon carbon double bonds in α,β- unsaturated ketones, and the activity of catalysts P-1.80-Ni, P-2 00-Ni or P-1.80(2 00) -Ni-M(M: Pd, Co, Cu) in the selective hydrogenation of carbon carbon double bonds in α,β-unsaturated carboxylic esters, were investigated systematically. According to the experimental results, the selectivities of these catalysts toward the hydrogenation of the carbon carbon double bonds of α,β-unsaturated keones or α,β-unsaturated carboxylic esters are 96%—100% or 100%, respectively. 展开更多
关键词 α β-unsaturated ketone Nickel boride α β-unsaturated carboxylic ester
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Syntheses and Structure-Odor Relationship of Some γ-Lactones
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作者 Wang Xiaolan,Tang Shixiong and Jiang Lasheng (Department of Chemistry , Nankai University, Tianjin) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第1期104-107,共4页
A lot of norbornene derivatives and lactones are widely used as fragrant components in food or cosmetics. We expected that a series of new compounds with better odor character could be obtained when these two skeleton... A lot of norbornene derivatives and lactones are widely used as fragrant components in food or cosmetics. We expected that a series of new compounds with better odor character could be obtained when these two skeleton structures were combined. Thus, a series of endoand exo-5,5-disubstituted-3-oxo-4-oxatricyclo[5,2,1,0;]dec-8-enes(Ⅰ) were synthesized. 展开更多
关键词 γ-lactones structure-odor synthesis
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Addition of Organosamarium Reagents toα, β-Unsaturated Esters
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作者 Yun Fa ZHENG Wei Liang BAO Yong Min ZHANG( Department of Chemistry, Zhejiang University, Xi Xi Campus, Hangzhou 310028 Li Shui Teachers College. Zhejiang 323000) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期5-8,共4页
Allylsamarium bromide reacts with Q, 6 -unsaturated esters and a -alkyloxy carbonyl α, β-unsaturated esters to give l,2-addition and 1 .4-addition products respectively.
关键词 SAMARIUM Grignard reagent conjugate addition α β-unsaturated esters.
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Cyclization Reaction of α-Triazolyl-α, β-unsaturated Ketones with Phenyl hydrazine
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作者 Guo Feng ZHAO Jun REN +1 位作者 Yu Chang LI Gui Yu JIN (Institute of Elemento-Organic Chemistry, National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期979-982,共4页
The reaction of α-triazolyl-α, β-unsaturated ketones with phenyl hydrazine was studied. The result indicated that cyclization took place and new heterocyclic compounds of substituted 4,5-2H-pyrazoles were obtained,... The reaction of α-triazolyl-α, β-unsaturated ketones with phenyl hydrazine was studied. The result indicated that cyclization took place and new heterocyclic compounds of substituted 4,5-2H-pyrazoles were obtained, whose structures and conformation were characterized by 1H NMR, IR, MS, elemental analysis and X-ray diffraction. 展开更多
关键词 α β-unsaturated ketones phenyl hydrazine TRIAZOLE CYCLIZATION PYRAZOLES
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Stereoselective Addition of N-Alkylhydroxylamines to α,β-Unsaturated Nitro Compounds
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作者 Ai Jun LI Ji Cheng CHU +2 位作者 Hong Sheng GUO Xue Qin ZHOU Dong Zhi LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第7期859-862,共4页
N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted additio... N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted addition mechanism was provided to explain the difference. 展开更多
关键词 N-Alkylhydroxylamines O-alkylhydroxylamines concerted addition mechanism α β-unsaturated nitro compounds stereoselectivity.
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Doebner condensation in ionic liquids [Bmim]BF_4 and [Bpy]BF_4 to synthesize α,β-unsaturated carboxylic acid
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作者 Dong Jiang Yuan Yuan Wang Yan Nan Xu Li Yi Dai 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第3期279-282,共4页
Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were ef... Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were efficient media for Doebner condensation, which could be recycled easily. The highest yields could reach 93% and 90% in [Bmim]BF4 and [Bpy]BF4, respectively. 展开更多
关键词 Ionic liquid Doebner condensation α β-unsaturated carboxylic acid DECARBOXYLATION
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Conjugate Addition Reactions of Functionalized Organozinc-copper Reagents to α,β-Unsaturated Esters
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作者 Yu Lai HU Jian Hua YU +3 位作者 Shi Yan YANG Yuan Qi YIN Tian Quan JIAO Jin Xian WANG(State. Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of sciences, Lanzhou 730000)(Department of Chemistry, 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第8期699-700,共2页
Functionalized organozinc reagents can easily conduct 1,4-addition reaction with unsaturated esters in the presence of Cu(OAc)2 and LiCl under very Anld conditions to give the products in excellent yields.
关键词 conjugate addition reaction organozinc reagents α β-unsaturated esters
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Organocatalyzed Highly Efficient Michael Addition of Malonate Derivatives to α,β-Unsaturated Ketones Using Chiral Schiff Bases
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作者 Yonghai Hui Jianzhong Zhang +1 位作者 Wanfu Sun Zhengfeng Xie 《Journal of Chemistry and Chemical Engineering》 2011年第9期847-853,共7页
An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temp... An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature. 展开更多
关键词 α β-unsaturated ketones cyanoacetate MALONATE Michael addition Schiffbase.
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A FACILE SYNTHESIS OF 2-AND 2,4-UNSATURATED AMIDES
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作者 Qi ZHONG Chang Qing LIU Chemistry Department,Yangzhou Teachers College,Yangzhou,225002 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期211-212,共2页
A convenient method for preparing unsaturated amides via telluro- nium salts employing solid potassium carbonate as a base with high stereo- selectivity in excellent yields has been developed.
关键词 A FACILE SYNTHESIS OF 2-AND 2 4-unsaturated AMIDES Za
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