中国化学快报

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STUDIES ON NUCLEOSIDES(Ⅲ).STEREOSELECTIVE SYNTHESES OF TRIAZOLINE-THIONE NUCLEOSIDES

Hong Ming CHEN, Jian ZHANG, Jian Min MAO, Meng Shen CAI

中国化学快报. 1994, 5(06): 455-456.

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Nine new nucleosides were prepared by the treatment of 3-[5-(3-pyridyl) tetrazol-2-yl-methylene]-4-aryl-1,2,4-triazole-5(4H)-thione (Ⅰ)with 1-O-trifluoroacetyl-2,3,5-O-tribenzoyl-β-D-ribofuranose (Ⅱ) in anhydrous CH₂Cl₂ in the presence of BF₃·Et₂O as catalyst.In this reaction,trifluoroacetoxy group used as leaving group is very effective.The structures and compositions were characterized by elemental analysis and spectroscopic methods.

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A CONVENIENT SYNTHESIS OF NEW HYDROXYL CYCLIC AZA COMPOUNDS

Guo Ping XUE, Sheng Hua LIU, En Qin FU, Han Sheng XU, Cheng Tai WU

中国化学快报. 1994, 5(06): 457-458.

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A convenient synthetic route to a series of hydroxyl cyclic di-and tri-aza compounds was described.Condensation of 1,3-dichloropropanol[2] with the appropriate disodium salts of N-tosylated di-and triamine in EtOH gave the corresponding 7-,8-and 10-membered di-and triamine cycles in reasonable yields.The tosyl groups were removed with 33% HBr-HOAc in ca. 90% yields.

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CHIRAL SYNTHESIS OF LEUKOTRIENE B₄

Yan Fang WANG, Jin Cui LI, Yu Lin WU, Wen Juan XIAO, Li Lan SHI, Yao Zeng HUANG

中国化学快报. 1994, 5(06): 459-460.

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A formal convergent synthesis of leukotriene B₄ has been carried out using D-mannitol and L-ascorbic acid as the chiral pool and formyl-enyl-olefination as the key step.

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ASYMMERIC SYNTHESIS OF 2-ARYLPROPIONIC ACIDS

He ZHAO, Yu Lin WU

中国化学快报. 1994, 5(06): 461-464.

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(S)-2-(6-methoxy-2-naphtyl)-propionic acid (S-Naproxen) 1 and (S)-2-(4-isobutylphenyl)-propionic acid (S-Ibuprofen) 2 have been synthesized enantioselectively. The steoreochemistry was established by a combination of Sharpless asymmetric dihydroxylation and catalytic hydrogenolysis of the chiral terminal epoxide.

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STUDIES ON GLYCOSIDES XⅢ.——HIGHLY STEREOSELECTIVE SYNTHESIS OF PER-O-BENZYLATED O-,S-α-D-GALACTOPYRANOSIDES AND GALACTOSYL CARBOXYUTES FROM PER-O-BENZYIATED GALACTOSYL TRIFLUOROACETATE

Jian Min MAO, Hong Ming CHEN, Jian ZHANG, Meng Shen CAI

中国化学快报. 1994, 5(06): 465-466.

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α Linked O-and S-galactopyranosides,and galactopyranosyl carboxylates were synthesized as the sole products from 2.3,4,6-tetra-O-benzyl-1-O-trifluoroacetyl-α-D-galacto-pyranose (2).The behavior of the nucleophiles and the two kinds of catalysts (BF₃·OEt₂ and TMSOTf) were discussed.

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REGIOSELECTIVE SYNTIIESIS OF OLIGONUCLEOTIDES

Zu Sheng XU, Zai Wan YANG

中国化学快报. 1994, 5(06): 467-470.

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A new bifunctional phosphitylating agent 9-fluorenemethylphosphorodiimidazolide has been synthesized,and its high regioselectivity was demonstrated by the synthesis of a series of oligonucleotides.

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SYNTHESIS OF ANALOGUES OF HUPERZINE A 2. The Preparation of Some Analogues with Huperzine A Skeleton

Xu Chang HE, Zhen Rong XU, Yun Long LI, Zhao Ying WANG, Dong Lu BAI

中国化学快报. 1994, 5(06): 471-474.

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Huperzine A (1),a new Lycopodium alkaloid isolated from Chinese traditional medicine Huperzia Serrata,is a potent acetylcholinesterase inhibitor and a promising drug candidate of treating Alzheimer's disease as well.Several analogues of huperzine A,compound 8,10,14,15 and 17 were prepared and their inhibitory activities of acetylcholinesterase were evaluated.

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SYNTHESIS OF 4-(2,3-DIMETHOXY-4-ISOPROPYLBENZYL)-3-ETHOXYCARBONYLMETHYL-2-CYCLOHEXENONE

Xue Chao WANG, Yu Xin CUI, Xin Fu PAN

中国化学快报. 1994, 5(06): 475-476.

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An eight-step synthesis of the key intermediate 5 for the total syntheses of Taxamairin A,B from catechol and 1,3-cyclohexandione was described.

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STEREOSELECTIVE AND MILD METHOD FOR THE SYNTHESIS OF α-D-MANNOPYRANOSIDES AND RELATED OLIGOSACCHARIDES IN HIGH YIELD

Zhong Jun LI, He Qing HUANG, Meng Shen CAI

中国化学快报. 1994, 5(06): 477-480.

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Model reaction of 1-O-(3,5-dinitrobenzoyl)-2,3,4,6-tetra-O-benzyl-α-D-mannopyranose 1 with a series of carboxylic acids,phenols,alcohols and saccharides respectively demonstrated that stereocontrolled mannosyl transfer with the retention of configuration at the anomeric center was best carried out in dichloromethane (-20℃→r.t.) with TMSOTf as the Lewis acid catalyst,DBMP as a deprotic agent and powdered 3A molecular sieves as a desiccating agent.Under these conditions,α-D-mannopyranosides and related oligosaccharides were obtained in good yields.

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TOTAL SYNTHESIS OF CURVULARIN-TYPE MACROLIDES 12-OXOCURVULARIN AND CITREOFURAN

Sheng LAI, Xiang GAO, Yoshikazu SHIZURI, Shosuke YAMAMURA

中国化学快报. 1994, 5(06): 481-484.

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The total synthesis of curvularin-type macrolides 12-oxocurvularin (1)and citreofuran (2)has been described.And the stereostructures of the two macrolides are unambiguously confirmed by this synthesis.

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THE REACTION OF 2,2-DIHYDROPOLYFLUOROALKANOATES WITH C-NUCLEOPHILES

Wei Yuan HUANG, Yan song LIU

中国化学快报. 1994, 5(06): 485-486.

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Ethyl 2,2-dihydropolyfluoroalkanoates reacted with C-nucleophiles in the presence of base under mild conditions to give the corresponding dehydrofluorination-addition products in good yields.

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A NOVEL SYNTHESIS OF α-ARYLSELENO-α-ACYL PHOSPHORANES AND ITS INTRAMOLECULAR WITTIG REACTION

Zhi Zhen HUANG, Xian HUANG

中国化学快报. 1994, 5(06): 487-488.

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可视化

α-Acyl phosphoranes can readily react with areneselenium cations,which can be obtained from diaryl diselenides by oxidative reaction,to give α-arylseleno-α-acyl phosphoranes in good yields.The α-arylseleno-α-acyl phosphoranes can undergo intramolecular Wittig reaction to afford a convenient synthesis of arylselenoacetylenes.

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6-O-DEMETHYL-(19S)-DIHYDROETORPHINE, A NEW SYNTHETIC COMPOUND, ISOLATED FROM CRUDE DIHYDROETORPHINE AS A MINOR BY-PRODUCT

Cheng Bin CUI, Xin Hui LUAN, Ming YANG, Zhi Wei YAO, Jian Ying DONG, Bing CAI, Bo Yi QIN

中国化学快报. 1994, 5(06): 489-492.

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可视化

6-O-Demethyl-(19S)-dihydroetorphine (1),a new synthetic compound having analgesic activity,has been isolated from crude dihydroetorphine as a minor by-product and its structure was determined by means of spectroscopic methods including 2D NMR techniques.

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SYNTHESIS OF DIISOFERULIC ACID

Chun Bo AI, Lian Niang LI

中国化学快报. 1994, 5(06): 493-496.

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Diisoferulic acid 3a which has the same configuration as salvianolic acid E was synthesized using isovanillin as starting material.Its Z isomer 3b was obtained during hydrolysis in a basic solution.

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7,2'-DIDESACETOXY AUSTROSPICATINE, A NEW TAXANOID FROM THE BARKS OF TAXUS WALLICHIANA ZUCC

Jun Zeng ZHANG, Qi Cheng FANG, Xiao Tian LIANG, Cun Heng HE

中国化学快报. 1994, 5(06): 497-500.

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可视化

A new taxanoid,7,2'-didesacetoxy austrospicatine,and five known taxanoids were isolated from the barks of Taxus wallichiana Zucc.Their structures were established by 1-and 2-D NMR and X-ray diffraction methods.

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PROTEIN IMMOBILIZATION ON CHEMICALLY MODIFIED CELLULOSE MEMBRANE AND AFFINITY SEPARATION OF α-INTERFERON

Zhen Hua SHANG, Wei GUO, Yi Nian YU, Ling Mo ZHOU

中国化学快报. 1994, 5(06): 501-504.

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Microfiltration cellulose membrane was chemically modified by epoxy method.Bovine serum albumin was successfully immobilized on the membrane after amination and diazotization.Efficient separation of α-interferon was carried out on the membrane with reactive dye as affinity ligand.

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HYDROGEN BOND IN β-CYCLODEXTRIN

Rui Qiang XIE, Wen Yi ZHAO, Chen Ho TUNG

中国化学快报. 1994, 5(06): 505-506.

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可视化

Intramolecular hydrogen bond of β-cyclodextrin was restudied by means of NMR techniques.

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AB INTIO THEORETICAL STUDY OF MIXED CLUSTER AICB

Guang Ping LI, An Min TIAN, Guo Sen YAN

中国化学快报. 1994, 5(06): 507-510.

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可视化

By use of ab initio and analytic energy gradient method, twelve optimized electronic states of AlCB, AlBC, BAlC in six geometric configurations are determined at all electron UHF(RHF)/6-31G^* level, their singles and doubles CI (CISD) energies are also obtained. The stabilities for the states of AlCB have been investigated based on the vibrational analysis,binding energy and fragmentation energy.The ground state is ³∑⁺ of AlCB (C_∞, r_AlC=1.7497, r_BC=1.3511 Å ω=206.7,799.5,1802.9 cm^-1, T_■=0), the second state is ¹A' of AlCB (C_s,r_AlC=1.9162,r_BC=1.3154 Å,∠ AlCB=179.8307°, ω=238.5,575.1,1767.5cm^-1, T_■=2432.84 cm^-1).The fragmentations of various states (fragmentation products are AlB,AlC, BC diatomic clusters and Al, B, C free atoms) of AlBC, AlCB, BAlC are discussed in detail.

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QUANTUM CHEMICAL STUDY ON THE MECHANISM OF PRODUCING OXYGENATES IN FISCHER-TROPSCH SYNTHESIS ON M/SiO₂ (M=Ni, Ru, Rh, Pd) CATALYSTS

Zheng Ping HAO, Tian Wei ZHU, Li Dun AN

中国化学快报. 1994, 5(06): 511-514.

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EHMO calculations and orbital analysis of fragments were performed for the synthetic reactions of oxygenates in Fischer-Tropsch synthesis using a butterfly model for four different metals (Ni,Ru,Rh,Pd) supported on SiO₂ as catalysts.Four processes:CO dissociation;coupling of CO and H to produce CHO;insertion of CO to M-CH₃;insertion of CH₂ to M-CH₃ have been calculated.We compared the degree of CO bond activation and the barriers of the foregoing processes for these four catalysts,it can be shown that Ni/SiO₂ is a methanation catalyst;Ru/SiO₂ and Rh/SiO₂ can produce C₂-oxygenated compound (acetaldehyde),especially Rh/SiO₂ is a good catalyst for producing it,and Pd/SiO₂ is a methanol synthesis catalyst.

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STUDY ON THE RELATIONSHIP BETWEEN MELTING POINT AND ACID DENATURING ACIDITY OF DNA BY ULTRAVIOLET SPECTROMETER

Yuan Zong LI, Xiang Dong LIU, Wen Bao CHANG, Yun Xiang CI

中国化学快报. 1994, 5(06): 515-518.

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可视化

The relationship between melting point and acid denaturing acidity of DNA was studied by ultraviolet spectrometer.According to our investigation there exists a good linear relationship between melting point and acid denaturing acidity of DNA.The acid denaturing acidity.which could be obtained easily.may be used in the field of biochemistry as an alternative to melting point.

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VAPORIZATION HEAT AT NORMAL BOILING POINT AND MOLECULAR TOPOLOGY FOR PARAFFINS

Deng Gao JIANG, Cai Rong ZHOU, Fu An WANG

中国化学快报. 1994, 5(06): 519-522.

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According to graph theory method,a new method is proposed for the prediction of vaporization heat at normal boiling point of paraffins with molecular structure,and it is compared with other methods.We predict the vaporization heat at normal boiling point for 57 different paraffins,and that is compared with experimental data,its overall absolute average deviation is 0.61%.The result is superior to other methods.

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RADICAL POLYMERIZATION OF VINYL MONOMER INITIATED BY CERIC ION/TARTARIC ACID

Jian Hua DONG, Da Hui LIU, Kun Yuan QIU, Xin De FANG

中国化学快报. 1994, 5(06): 523-526.

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The polymerization of acrylamide and acrylonitrile using ceric ion as initiator can be promoted greatly by the tartaric acid.The kinetics of acrylamide polymerization initiated by ceric ion/tartaric acid has been studied.The presence of the species of tartaric acid in polyacrylonitrile produced by using ceric ion/tartaric acid as initiator has been confimed by FT-IR analysis.

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ACIDITY AND CATALYTIC ACTIVITY OF KEGGIN STRUCTURE HETEROPOLYACIDS——EFFECT OF CENTRAL ATOM IN H_αXW₁₂O₄₀

Chang Wen HU, Yan Yong LIU, En Bo WANG, M. HASHIMOTO, T. OKUHARA, M. MISONO

中国化学快报. 1994, 5(06): 527-528.

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In this paper,the acidity function,Ho,of Keggin structure heteropolyacids H₀XW₁₂O₄₀ (X=P,Si,Ge,B,Co) has been examined in acetonitrile solution by the UV-Hammett method.The dependence of catalytic activity on the acid strength in four different type of reactions was studied.

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APPLICATION OF WAXD AND SAXS TO STRUCTURAL ANALYSIS OF PA1010+BMI

Hong Fang ZHANG, LI Hua ZHANG, Bao Quan YANG, Zhi Shen MO

中国化学快报. 1994, 5(06): 529-530.

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WAXD and SAXS for PA1010+BMI system have been measured.The results obtained with the help of Ruland and 1D EDCF,showed that W_c,x,the long period L and the thickness of the crystal lamellae d_o decreased with BMI content at PA10101+BMI system.Comparing both experimental and calculated density ρ_c values indicated that the values were of better conformity.Adding BMI into PA1010 caused an increase in distortion.The results from SAXS analysis have also led to the conclusion that a crystal-amorphous interphase could exist in lamellae of semicrystalline polymers and a three-phase model instead of traditional two-phase model should be used.

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CATALYTIC PROPERTIES OF SILICA-SUPPORTED POLY-γ-AMINOPROPYLSILOXANE-RHODIUM-COBALT BIMETALLIC COMPLEX FOR HYDROFORMYLATION

Li Ming TANG, Dan WU, Mei Yu HUANG, Ying Yan JIANG

中国化学快报. 1994, 5(06): 531-532.

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Hydroformylation of methyl methacrylate with a conversion of 95.6% and selectivity of 92.8% for the normal product,methyl β-formylisobutyrate has been achieved when the reaction was catalyzed by a silica-supported poly-γ-aminopropylsiloxane-rhodium-cobalt bimetallic complex (abbreviated as SiO₂-NH₂-Rh-Co).The catalyst was stable during the reaction and could be used repeatedly.

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HEATS OF INTERACTION OF ORGANIC BASES WITH POLYMER PROTECTED CATALYST PVC-AlCl₃

Xiang Dong ZHANG, Qi Tao LIU, Wen Hua TAN, Yu SONG

中国化学快报. 1994, 5(06): 533-536.

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Heats of immersion into a series of organic bases at 25℃ are reported for polymer protected catalyst PVC-AlCl₃.There is a good correlation between the heats of immersion of PVC-AlCl₃ and tbennochemical measurements of BF₃ or SbCl₅.The results have shown that the reaction of PVC-AlCl₃ with various bases is essentially Lewis acid-base interaction and the surface acidity of PVC-AlCl₃ is mainly attributed to Lewis acidity.

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SYNTHESIS AND COMPLEXATION PROPERTIES OF NEW DIOXO TETRAAMINE LIGANDS WITH 8-METHYL QUINOLINE AS FUNCTIONAL PENDANT(S)

Dao Li AN, Xian He BU, Hua Kuan LIN, Yu LIU, Yun Ti CHEN

中国化学快报. 1994, 5(06): 537-540.

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Two new dioxo tetraamine liganda L₁ and L₂ have been synthesized and characterized by ¹H NMR,IR,MS and elemental analysis.Their protonation constants and complex formation constants with Cu²⁺ have been determined by potentiometric titration.

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SYNTHESIS, SURFACE POTENTIAL AND NONLINEAR OPTICAL PROPERTIES OF NEW AMPHIPHILIC PORPHYRINS

Xue Qun ZHANG, Dong XIAO, Yu WEI, Xuan Jie WU, Gui Guang XIONG

中国化学快报. 1994, 5(06): 541-542.

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A new kind of amphiphilic porphyrin containing only one carboxyl on the β point of porphyrin ring was synthesized.The surface potential and SHG (Second Harmonic Generation) efficiency of monolayer were measured and the relationship between the surface potential,SHG and the structure of molecule was discussed.

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SYNTHESIS AND SPECTRA STUDIES OF TRANSITION METAL COMPLEXES DERIVED FROM 2, 4-DINITROPHENYL HYDRAZINE

BO WANG, Jin Xia LIU, Shi Yan YANG, Dao Sen JIN, Yu Lin LI

中国化学快报. 1994, 5(06): 543-546.

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可视化

Complexes of salicylaldehyde-2,4-dinitrophenylhydrazine (HL) of the type ML₂,[M=Co^Ⅱ,Ni^Ⅱ,Cu^Ⅱ,Zn^Ⅱ and Mn^Ⅱ] have been prepared and characterized by elemental analysis,molar conductance,magnetic susceptibility,TG-DTA,electronic,IR and XPS methods.The chelating models are discussed.

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SYNTHESIS AND ¹⁸³W NMR CHARACTERIZATI0N OF α-[P₂W₁₅)O₆₂Ti₃]^12- HFTEROPOLYANION

Lu NENG, Jing Fu LIU

中国化学快报. 1994, 5(06): 547-548.

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A trisubstituted Dawson anion with tetravalent heteroelement titanium has been synthesized from the lacunary precursor Na₁₂[α-P₂W₁₅O₅₆].24H₂O and characterized by IR.UV.and ¹⁸³W NMR spectnm.¹⁸³W NMR of the title anion consists of three lines (intensity ratio 1:2:2) as expected for the trisubstituted α-Dawson anion.

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1994年, 第5卷, 第06期　刊出日期：1994-06-20

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本期目录

1994年, 第5卷, 第06期 刊出日期：1994-06-20

1994年, 第5卷, 第06期　刊出日期：1994-06-20