C-3 epimeric secondary zinc reagents 2a/b were prepared from either diastereoisomeric iodide 3a or 3b using DMF as solvent, and characterised by 1H NMR methods. Palladium catalysed cross couplings and copper promoted allylations yielded protected β-methyl substituted amino acids.
{"title":"Palladium(0) catalysed and copper(I) promoted reactions of the secondary zinc reagent derived from L-threonine","authors":"Ian J. Wilson, R. Jackson","doi":"10.1039/B208667K","DOIUrl":"https://doi.org/10.1039/B208667K","url":null,"abstract":"C-3 epimeric secondary zinc reagents 2a/b were prepared from either diastereoisomeric iodide 3a or 3b using DMF as solvent, and characterised by 1H NMR methods. Palladium catalysed cross couplings and copper promoted allylations yielded protected β-methyl substituted amino acids.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"178 1","pages":"2845-2850"},"PeriodicalIF":0.0,"publicationDate":"2002-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79947471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
1,3,4-Thiadiazolium-3-methanide 1,3-dipole 6 and the 2,5-diphenyl and 2,5-dimethyl derivatives, 4 and 5, were generated at −60 °C in dichloromethane. Cycloaddition reactions with substituted alkenes gave many new derivatives of the pyrrolo[2,1-b][1,3,4]thiadiazole ring system. The first examples of a bowl-shaped tricyclic nitrogen-sulfur analogue of the tripentagon bowl, a 3,4,10-triaza-6-thiatricyclo[6,3,0,03,7]undecane ring system were obtained from N-substituted maleimide dipolarophiles. The reactions displayed predominantly endo-stereochemistry but with decreasing size of the substituent at the incipient 7a-fusion bridgehead in the cycloaddition transition state, the extent of exo-cycloaddition increased. The cycloadduct endo ∶ exo ratio was reduced from exclusively endo to ca. 2 ∶ 1 on changing the 1,3-dipole from the 2,5-diphenyl derivative 4 to the unsubstituted case 6. X-Ray crystal structures are reported for 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-endo-6,7-N-methyldicarboxyimide 7a, 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-endo-6,7-N-phenyldicarboxyimide 9e and 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-7-endo-carbonitrile 13.
1,3,4-噻二唑-3-甲烷- 1,3-偶极子- 6及其衍生物2,5-二苯基和2,5-二甲基衍生物4和5在- 60℃的二氯甲烷中生成。与取代烯烃的环加成反应产生了许多新的吡咯[2,1-b][1,3,4]噻二唑环体系衍生物。以n-取代马来酰亚胺偶极试剂为原料，首次得到了碗状的氮-硫三环类似物，即3,4,10-三氮杂-6-硫三环[6,3,0,03,7]十一烷环体系。反应以内立体化学为主，但随着环加成过渡态7a融合桥头堡取代基尺寸的减小，外环加成程度增加。将2,5-二苯基衍生物4的1,3偶极子改变为未取代的6时，环加合物的内do∶外显子比由纯内do∶外显子降至约2∶1。报道了2,7a-二苯基-5,6,7,7a-四氢吡咯[2,1-b][1,3,4]噻二唑-内-6,7- n -甲基二羰基亚胺7a, 2,7a-二苯基-5,6,7,7a-四氢吡咯[2,1-b][1,3,4]噻二唑-内-6,7- n -苯基二羰基亚胺9e和2,7a-二苯基-5,6,7,7a-四氢吡咯[2,1-b][1,3,4]噻二唑-7-内-碳腈13的x射线晶体结构。
{"title":"A new tricyclic ring and a nitrogen–sulfur analogue of the tri-pentagon bowl: cycloaddition reactions of the unstablised 1,3,4-thiadiazolium-3-methanide 1,3-dipole: steric influences on the endo-effect: substituted pyrrolo[2,1-b]-1,3,4-thiadiazole systems: azolium 1,3-dipoles","authors":"R. N. Butler, G. Smyth, P. McArdle, D. Cunningham","doi":"10.1039/B208544P","DOIUrl":"https://doi.org/10.1039/B208544P","url":null,"abstract":"1,3,4-Thiadiazolium-3-methanide 1,3-dipole 6 and the 2,5-diphenyl and 2,5-dimethyl derivatives, 4 and 5, were generated at −60 °C in dichloromethane. Cycloaddition reactions with substituted alkenes gave many new derivatives of the pyrrolo[2,1-b][1,3,4]thiadiazole ring system. The first examples of a bowl-shaped tricyclic nitrogen-sulfur analogue of the tripentagon bowl, a 3,4,10-triaza-6-thiatricyclo[6,3,0,03,7]undecane ring system were obtained from N-substituted maleimide dipolarophiles. The reactions displayed predominantly endo-stereochemistry but with decreasing size of the substituent at the incipient 7a-fusion bridgehead in the cycloaddition transition state, the extent of exo-cycloaddition increased. The cycloadduct endo \u0000∶ \u0000exo ratio was reduced from exclusively endo to ca. 2 ∶ 1 on changing the 1,3-dipole from the 2,5-diphenyl derivative 4 to the unsubstituted case 6. X-Ray crystal structures are reported for 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-endo-6,7-N-methyldicarboxyimide 7a, 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-endo-6,7-N-phenyldicarboxyimide 9e and 2,7a-diphenyl-5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3,4]thiadiazole-7-endo-carbonitrile 13.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"65 1","pages":"2851-2860"},"PeriodicalIF":0.0,"publicationDate":"2002-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89832220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Treatment of α-phenylsulfanyl esters 11–14 with one equivalent of difluoroiodotoluene 3a produced the α-fluoro sulfides 17–20 in good overall yield through a Fluoro-Pummerer reaction. A second equivalent of reagent produced α,α-difluoro sulfides and a third led to α,α-difluoro sulfoxides. An identical pattern of reactivity was observed with the α-phenylsulfanyl lactone 26. This sequential fluorination–oxidation behaviour was exploited in the one-pot synthesis of 3-fluoro-2(5H)-furanone 33 starting from α-phenylsulfanylbutyrolactone 32.
{"title":"Fluorination of α-phenylsulfanyl esters using difluoroiodotoluene","authors":"W. Motherwell, M. Greaney, D. Tocher","doi":"10.1039/B209079A","DOIUrl":"https://doi.org/10.1039/B209079A","url":null,"abstract":"Treatment of α-phenylsulfanyl esters 11–14 with one equivalent of difluoroiodotoluene 3a produced the α-fluoro sulfides 17–20 in good overall yield through a Fluoro-Pummerer reaction. A second equivalent of reagent produced α,α-difluoro sulfides and a third led to α,α-difluoro sulfoxides. An identical pattern of reactivity was observed with the α-phenylsulfanyl lactone 26. This sequential fluorination–oxidation behaviour was exploited in the one-pot synthesis of 3-fluoro-2(5H)-furanone 33 starting from α-phenylsulfanylbutyrolactone 32.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"58 1","pages":"2809-2815"},"PeriodicalIF":0.0,"publicationDate":"2002-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91003173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Sharpless asymmetric aminohydroxylation","authors":"J. Bodkin, M. McLeod","doi":"10.1039/B111276G","DOIUrl":"https://doi.org/10.1039/B111276G","url":null,"abstract":"","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"1 1","pages":"2733-2746"},"PeriodicalIF":0.0,"publicationDate":"2002-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89391634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Gabbutt, J. Hepworth, B. Heron, Samantha L. Pugh
Enamino acids derived from 1,2-dimethylaminomethylene- or 1,2-hydroxymethylene-carbonyl compounds and amino acids undergo a decarboxylative cyclisation to pyrroles, isoindoles and other fused pyrroles. A two atom ring expansion occurs preferentially with enamino acids from cyclohexane-1,3-diones and α-alkyl-α-amino acids leading to oxocino[2,3-c]pyrroles.
{"title":"A facile route to pyrroles, isoindoles and hetero fused analogues","authors":"C. Gabbutt, J. Hepworth, B. Heron, Samantha L. Pugh","doi":"10.1039/B209255G","DOIUrl":"https://doi.org/10.1039/B209255G","url":null,"abstract":"Enamino acids derived from 1,2-dimethylaminomethylene- or 1,2-hydroxymethylene-carbonyl compounds and amino acids undergo a decarboxylative cyclisation to pyrroles, isoindoles and other fused pyrroles. A two atom ring expansion occurs preferentially with enamino acids from cyclohexane-1,3-diones and α-alkyl-α-amino acids leading to oxocino[2,3-c]pyrroles.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"45 1","pages":"2799-2808"},"PeriodicalIF":0.0,"publicationDate":"2002-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88298042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The photoinduced reactions of 1- and 2-nitronaphthalene (1- and 2-NN) and 1-methoxy-4-nitronaphthalene (MNN) in the presence of DABCO, triethylamine (TEA) and diethylamine (DEA) in neat acetonitrile and acetonitrile–water were studied by UV–vis spectroscopy and conductometry upon excitation by ns laser pulses at 354 nm. The rate constant of quenching of the nitronaphthalene triplet state by the amines is close to the diffusion-controlled limit in deoxygenated acetonitrile and smaller (kq ≊ 2 × 109 M−1 s−1) in the presence of water (5 M). Electron transfer yields the nitronaphthalene radical anions which were observed as secondary transients with maxima at 390 nm. At higher TEA or DEA concentrations (>1 mM) nitronaphthalene radicals are formed in a second, delayed event by reduction of the nitronaphthalene ground state involving the α-aminoalkyl radicals. The nitronaphthalene radicals react via second-order termination yielding nitrosonaphthalenes and further products. The photoinduced electron transfer and subsequent radical disproportionation reactions are supported by time-resolved conductometric measurements. The mechanism of the two-step reduction reactions in the presence of TEA or DEA and the effects of amine concentration, oxygen and water are discussed.
{"title":"Photoreduction induced by electron transfer from di- and trialkylamines to the triplet state of nitronaphthalenes in polar media","authors":"H. Görner, D. Döpp","doi":"10.1039/B107328C","DOIUrl":"https://doi.org/10.1039/B107328C","url":null,"abstract":"The photoinduced reactions of 1- and 2-nitronaphthalene (1- and 2-NN) and 1-methoxy-4-nitronaphthalene (MNN) in the presence of DABCO, triethylamine (TEA) and diethylamine (DEA) in neat acetonitrile and acetonitrile–water were studied by UV–vis spectroscopy and conductometry upon excitation by ns laser pulses at 354 nm. The rate constant of quenching of the nitronaphthalene triplet state by the amines is close to the diffusion-controlled limit in deoxygenated acetonitrile and smaller (kq \u0000≊ 2 × 109 M−1 s−1) in the presence of water (5 M). Electron transfer yields the nitronaphthalene radical anions which were observed as secondary transients with maxima at 390 nm. At higher TEA or DEA concentrations (>1 mM) nitronaphthalene radicals are formed in a second, delayed event by reduction of the nitronaphthalene ground state involving the α-aminoalkyl radicals. The nitronaphthalene radicals react via second-order termination yielding nitrosonaphthalenes and further products. The photoinduced electron transfer and subsequent radical disproportionation reactions are supported by time-resolved conductometric measurements. The mechanism of the two-step reduction reactions in the presence of TEA or DEA and the effects of amine concentration, oxygen and water are discussed.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"28 1","pages":"120-125"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74521543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aqueous assemblies of adamantyl-derivatized poly(propylene imine) (PPI) dendrimers and B-cyclodextrin (B-CD) have been used as nanoreactors in the preparation of gold and platinum nanoparticles in water. These particles have been formed by the reduction of aurate or platinate anions in the presence of the generation 4 (4·(B-CD)32) and 5 ( 5·(B-CD)40) assemblies. Lower generation assemblies did not provide stable nanoparticles. A kinetic model is proposed in which the particles form inside the dendrimer assemblies owing to preferred nucleation as a result of the electrostatic attraction between the polycationic core and the metallate anions. The persistent shape of the adamantyl-derivatized dendrimers and the dense shell of adamantyl-B-CD complexes provide a kinetic barrier for nanoparticle escape thus prolonging their lifetime. Exchange of the dendrimers for a cationic disulfide provided stable, water-soluble metal nanoparticles without change of their size distribution.
以金刚烷基衍生化聚丙烯亚胺(PPI)树状大分子和b -环糊精(B-CD)为纳米反应器，在水中制备了金和铂纳米粒子。这些粒子是在第4代(4·(B-CD)32)和第5代(5·(B-CD)40)离子存在下由金酸盐或铂酸盐阴离子还原而成的。较低一代的组件不能提供稳定的纳米颗粒。提出了一种动力学模型，其中由于多阳离子核和金属阴离子之间的静电吸引而形成的优先成核，粒子在树状大分子内形成。金刚烷基衍生的树状大分子的持久形状和金刚烷基- b - cd络合物的致密外壳为纳米颗粒的逃逸提供了动力学屏障，从而延长了它们的寿命。将树状大分子交换为阳离子二硫化物提供了稳定的水溶性金属纳米颗粒，而不改变其尺寸分布。
{"title":"Dendrimer–cyclodextrin assemblies as stabilizers for gold and platinum nanoparticles","authors":"J. Michels, J. Huskens, D. Reinhoudt","doi":"10.1039/B108026A","DOIUrl":"https://doi.org/10.1039/B108026A","url":null,"abstract":"Aqueous assemblies of adamantyl-derivatized poly(propylene imine) (PPI) dendrimers and B-cyclodextrin (B-CD) have been used as nanoreactors in the preparation of gold and platinum nanoparticles in water. These particles have been formed by the reduction of aurate or platinate anions in the presence of the generation 4 (4·(B-CD)32) and 5 ( 5·(B-CD)40) assemblies. Lower generation assemblies did not provide stable nanoparticles. A kinetic model is proposed in which the particles form inside the dendrimer assemblies owing to preferred nucleation as a result of the electrostatic attraction between the polycationic core and the metallate anions. The persistent shape of the adamantyl-derivatized dendrimers and the dense shell of adamantyl-B-CD complexes provide a kinetic barrier for nanoparticle escape thus prolonging their lifetime. Exchange of the dendrimers for a cationic disulfide provided stable, water-soluble metal nanoparticles without change of their size distribution.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"56 1","pages":"102-105"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84462012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High-resolution electron momentum spectroscopy of molecules","authors":"M. Brunger, W. Adcock","doi":"10.1039/B100700I","DOIUrl":"https://doi.org/10.1039/B100700I","url":null,"abstract":"","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"87 1","pages":"1-22"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85940375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Computations were performed on idealized retrosynthetic routes towards two model buckybowl compunds, sumanene (I) and pinakene (II). Two possible paths for sumanene (I) and six for pinakene (II) were analyzed. The computational results unequivocally predict that benzannulation is a significantly easier process compared to cyclopentannulation in the ring closure strategies in both cases. The suitability of the theoretical models for obtaining reliable trends is assessed and generalizations for the synthetic strategies directed towards buckybowls and C60 were made.
{"title":"Ring closure synthetic strategies toward buckybowls: benzannulation versus cyclopentannulation","authors":"T. C. Dinadayalane, U. Priyakumar, G. Sastry","doi":"10.1039/B108030J","DOIUrl":"https://doi.org/10.1039/B108030J","url":null,"abstract":"Computations were performed on idealized retrosynthetic routes towards two model buckybowl compunds, sumanene (I) and pinakene (II). Two possible paths for sumanene (I) and six for pinakene (II) were analyzed. The computational results unequivocally predict that benzannulation is a significantly easier process compared to cyclopentannulation in the ring closure strategies in both cases. The suitability of the theoretical models for obtaining reliable trends is assessed and generalizations for the synthetic strategies directed towards buckybowls and C60 were made.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"2015 1","pages":"94-101"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73392614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The ion transport ability in a planar phospholipid bilayer, of two p-tert-butylcalix[4]arene-crown-5 derivatives (1, 2), a p-tert-butylcalix[5]arene ester 3, dibenzo-18-crown-6, and valinomycin have been investigated using a voltage clamp method. Membrane current measurements showed that the synthetic calixarene ionophores except for dibenzo-18-crown-6, show ion transport activities for K+ in the bilayer membranes. The order of K+ transport activities of the compounds was valinomycin >1 > 3 > 2. From the measurements of reversal potentials, the relative ion permeability across the bilayer was determined for 1, 3 and valinomycin. Both 1 and 3 showed ion transport selectivity for K+, while valinomycin showed ion transport selectivity for Rb+. Among the calixarene ionophores, compound 1 showed the highest K+ conductivity and K+/Na+ selectivity. Although the K+/Na+ selectivity of 1 is less than that of valinomycin by a factor of ca. 2, calix[4]arene-based ionophore 1 has the potential for use as a synthetic K+ carrier in phospholipid bilayer membranes.
{"title":"Selective transport of potassium ions across a planar phospholipid bilayer by a calix[4]arene-crown-5 as a synthetic carrier","authors":"T. Jin","doi":"10.1039/B106153B","DOIUrl":"https://doi.org/10.1039/B106153B","url":null,"abstract":"The ion transport ability in a planar phospholipid bilayer, of two p-tert-butylcalix[4]arene-crown-5 derivatives (1, 2), a p-tert-butylcalix[5]arene ester 3, dibenzo-18-crown-6, and valinomycin have been investigated using a voltage clamp method. Membrane current measurements showed that the synthetic calixarene ionophores except for dibenzo-18-crown-6, show ion transport activities for K+ in the bilayer membranes. The order of K+ transport activities of the compounds was valinomycin >1 > 3 > 2. From the measurements of reversal potentials, the relative ion permeability across the bilayer was determined for 1, 3 \u0000and valinomycin. Both 1 and 3 showed ion transport selectivity for K+, while valinomycin showed ion transport selectivity for Rb+. Among the calixarene ionophores, compound 1 showed the highest K+ conductivity and K+/Na+ selectivity. Although the K+/Na+ selectivity of 1 is less than that of valinomycin by a factor of ca. 2, calix[4]arene-based ionophore 1 has the potential for use as a synthetic K+ carrier in phospholipid bilayer membranes.","PeriodicalId":17267,"journal":{"name":"Journal of The Chemical Society-perkin Transactions 1","volume":"71 1","pages":"151-154"},"PeriodicalIF":0.0,"publicationDate":"2002-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87776566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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