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THE STUDY OF ENZYMATIC SYNTHESIS OF MACROCYCLIC LACTONES
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《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第4期251-252,共2页
The effects of the chain length and stereo-factor of substrates and solvents on the lipase catalysed lactonization of ω-hydroxy-ester were studied, And also the catalytic effects of various enzymes were compared.
关键词 PPL THE study OF ENZYMATIC synthesis OF MACROCYCLIC LACTONES
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THE STUDY ON THE WATER SOLUBLE PEPTIDES IN PAPAVER SOMNIFERUM POLLEN EXTRACTION,PURIFICATION,SEQUENCE DETERMINATION AND SYNTHESIS
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作者 Jia Xi XU Sheng JIN Department of Chemistry Peking University Beijing 100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期213-214,共2页
Four peptides PSPP1,PSPP2,PSPP3 and PSPP4 were purified from the water-extract of Papaver somniferum pollen.Their sequences,with 21,17,13 and 16 amino acid residues respectively,have been determined by Edman degradati... Four peptides PSPP1,PSPP2,PSPP3 and PSPP4 were purified from the water-extract of Papaver somniferum pollen.Their sequences,with 21,17,13 and 16 amino acid residues respectively,have been determined by Edman degradation-N-terminal dansylation.PSPP2, PSPP3 and PSPP4 were synthesized using solid phase method.The immunopromotive activities of PSPP1,PSPP2,PSPP3,PSPP4 and the initially separated sample PSPP have been also observed by the methods of counting erythrocyte rosette forming cells(ERFC) and T-lymphocyte transformation test in vitro. 展开更多
关键词 PSPP Th THE study ON THE WATER SOLUBLE PEPTIDES IN PAPAVER SOMNIFERUM POLLEN EXTRACTION PURIFICATION SEQUENCE DETERMINATION AND synthesis Gly
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THE ADVANCES IN SYNTHESIS AND STUDY OF NEW NUCLIDES IN CHINA
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作者 Wei Baowen, Luo Yixiao and Jin Genming(Institute of Modern Physics. CAS) 《Bulletin of the Chinese Academy of Sciences》 1995年第1期45-49,共5页
This paper introduces the importance of synthesis and study of new nuclides far from the stability line. Following the example of new nuclides 208Hg, 185Hf and 237Th, which were synthesized for the first time by the s... This paper introduces the importance of synthesis and study of new nuclides far from the stability line. Following the example of new nuclides 208Hg, 185Hf and 237Th, which were synthesized for the first time by the scientists in the Institute of Modern Physics, the progress of physics and technology in this aspect in our country are summarized. This paper also outlines a proposal about farther development of the synthesis and study of new nuclides and the construction of relevant key facilities in our country at the beginning of the next century. 展开更多
关键词 THE ADVANCES IN synthesis AND study OF NEW NUCLIDES IN CHINA HG LINE
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Experimental study on effect of endothelin in the proliferation and collagen synthesis of human scar-derived fibroblasts
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作者 刘德伍 《外科研究与新技术》 2003年第2期124-125,共2页
Objective To investigate the role of endothelin(ET) in the proliferation and collagen synthesis of human scar-derived fibroblasts and the moduktion of its antagonists such as nitric oxide(NO), tetrandrine ( Tet). Meth... Objective To investigate the role of endothelin(ET) in the proliferation and collagen synthesis of human scar-derived fibroblasts and the moduktion of its antagonists such as nitric oxide(NO), tetrandrine ( Tet). Methods With the cultured fibroblasts from the scarring tissue, the cell pdiferation was determined by[3H]-TdR incorporation, while the collagen synthesis was evaluated by[3H]-proline incorporation. Results The ET-1 was significantly increasing the proliferation and collagen synthesis of human scar-derived fibroblasts. The values of [3H]-TdR absorption in the 2.5 ng/ml,25 ng/ml and 100 ng/ml of ET-1 groups were 1.8 times,4 times and 4.9 times more than in the control group, respectively(P【0. 01),while the values of the [3H]-proline incorporation were 1.1 times,3.1 times and 3.8 times respectively(P【0.01). The fibroblasts, treated with 50 μg/ml of S-nitroso-N-acetyl penicillamine(SNAP), were no detectable effect on the basal level of DNA synthesis,but produced decreasing effect on the 展开更多
关键词 of Experimental study on effect of endothelin in the proliferation and collagen synthesis of human scar-derived fibroblasts
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 The synthesis of 9 H 7 H-12-Eudesmanoic Acid Methyl Ester Dien-5 study on the Total synthesis of 3-Oxo-9 Acetoxyilicic Acid Acetoxy-3
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STUDY ON THE SYNTHESIS OF A NEW TYPE OF PHOSPHORUS HETEROCYCLIC COMPOUNDS-PYRAZOLO[3,4-d]-1,3,2-DIAZAPHOSPHORIN-6-ONE 被引量:2
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作者 Ru Yu CHEN Jian Wu WANG Institute of Elemento-Organic Chemistry,Nankai University,Tianjin 300071,China 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期59-60,共2页
1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3,4-d]-oxazinone(1) with amines in benzene.The compound 2 was refluxed with excess LiAlH_4 in a mixture of ... 1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3,4-d]-oxazinone(1) with amines in benzene.The compound 2 was refluxed with excess LiAlH_4 in a mixture of THF and ether,one of the two carbamoyl groups in the molecule 2 was reduced selectively.As the results,1-substituted-5- benzylamino-4-pyrazolecarboxamides(3)were obtained.Compounds 3 reacted with Cl_2PPh-X,or P(NET_2)_3,producing the title compounds(4). The conditions of the reactions were studied. 展开更多
关键词 DIAZAPHOSPHORIN-6-ONE study ON THE synthesis OF A NEW TYPE OF PHOSPHORUS HETEROCYCLIC COMPOUNDS-PYRAZOLO[3 4-d
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Synthesis and Luminescence Study of Europium Complexes with Carboxylic Acid and 1,10-Phenanthroline Ligands
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作者 QIAN Dong-jin and ZHANG Shu-zhen (Department of Chemistry, Shandong University, Jinan, 250100)CHEN Zhong (Department of Chemistry, Teacher s College, Yangzhou University, Yangzhou, 225002)J. Van Houten(Department of Chemistry, St. Michael’s College, Winooski Park, Colchester, VT05439, U. S. A. ) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第3期181-187,共7页
A series of euroPium(Ⅱ)eomPlexes with earboxylie aeids andl,10-Phenantl飞ro-line:Eu(L):·pllen·jHoO,wl:ereL-formate,3-hydroxy-4-metlloxybenzoate,4一metl、oxybenzoate,4一ehloroPhenoxyaeetate,and diPI、enylaee... A series of euroPium(Ⅱ)eomPlexes with earboxylie aeids andl,10-Phenantl飞ro-line:Eu(L):·pllen·jHoO,wl:ereL-formate,3-hydroxy-4-metlloxybenzoate,4一metl、oxybenzoate,4一ehloroPhenoxyaeetate,and diPI、enylaeetate,were synthesizedand el、araeterized by elemental analysis,UV sPeetrum,IR speetrum and melting point.IR da亡a eonfirmed tllat euroPium 15 eoordinated wirh 0 donor atoms in earboxy!ie aeidand N donor atoms inl,10一phenanthroline.A strong ligand一loealized absorption at270 nm!ed to a series of meta!一eentered emission bands between 580 and 710 nm as-signedto ~5D_0-7F_(0.1.2.3.) 展开更多
关键词 Europium complexes synthesis Luminescence study
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Synthesis and High Pressure Study on Ca_(1-x)Ln_xSiO_3
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作者 Jinghai YANG Juyuan ZHANG Yizhi GENG (Institute of Solid State Physics, Siping Normal College, Siping, 136000, China)Bin YAO (State Key Lab. for RSA, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110015, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第4期307-309,共3页
In this paper, for the first time, Ca1-xLnxSiO3 (Ln=Y. La, x=0.1, 0.2) was synthesized with three methods of high temperature (HT) under atmospheric pressure (AP), high temperature (HT) combined with high pressure (HP... In this paper, for the first time, Ca1-xLnxSiO3 (Ln=Y. La, x=0.1, 0.2) was synthesized with three methods of high temperature (HT) under atmospheric pressure (AP), high temperature (HT) combined with high pressure (HP) and sol-gel method. The sample obtained at the stable range of 4.3-5.0 GPa pressure and 1050-1100℃ temperature with HT and HP method has a cubic perovskite structure, which has the minimum lattice parameter of 0.3535 nm so far,the sample with triclinic structure was obtained by sintering at atmosphere, and the sample synthesized with sol-gel method has monoclinic structure. SEM analysis shows that rare earth ions take the lattice site of Ca, but the distribution of rare earth ions in the samples synthesized with HT and HP is not homogeneous. 展开更多
关键词 synthesis and High Pressure study on Ca La SiO x)LnxSiO3
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STUDY ON THE SYNTHESIS OF BRASSINOLIDE AND RELATED COMPOUNDS 15.FORMAL SYNTHESIS OF BRASSINOLIDE VIA STEREOSELECTIVE SULFENATE-SULFOXIDE TRANSFORMATION
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作者 Wei Sham ZHOU Zheng Wu SHEN Shanghai Institute of Organic Chemistry,Chinese Academy of Science,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第2期111-114,共4页
A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 an... A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 and(24R)-22-E-24-sulfoxide 9,respectively to (22S)-23-E-24-methyl compound 4. 展开更多
关键词 KBr IR OH cm THF study ON THE synthesis OF BRASSINOLIDE AND RELATED COMPOUNDS 15.FORMAL synthesis OF BRASSINOLIDE VIA STEREOSELECTIVE SULFENATE-SULFOXIDE TRANSFORMATION VIA
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STUDY ON THE SYNTHESIS AND PROPERTIES OF MACRORETICULAR IPN POLYACRYLAMIDE—POLY(VINYL—ETHYLENEDIAMINE)CHELATE SORBENTS
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作者 Yan Feng LI Ren Xi ZHUO Dept.of Chemistry,Wuhan Univ.,Wuhan 430072 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期619-620,共2页
A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelate sorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The new chelate sorbent showed good sorption properties for auri... A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelate sorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The new chelate sorbent showed good sorption properties for auric and platinic ions. 展开更多
关键词 IPN study ON THE synthesis AND PROPERTIES OF MACRORETICULAR IPN POLYACRYLAMIDE VINYL MR ETHYLENEDIAMINE)CHELATE SORBENTS POLY
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SYNTHESIS OF N,N'-DISUBSTITUTED MONOTHIOXAMIDE AND STUDY OF THEIR REACTIONS WITH DIAMINES
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作者 Yu Ren YUAN Da Qing SUN Ke Qian CHEN Zhong E LU Department of Chemistry, Suzhou University, Suzhou, 215006 Hal Kang YANG The Central Laboratory, Suzhou University, Suzhou, 215006 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期379-380,共2页
In this paper, six N,N'-disubstituted aonothioxamides were synthesized and the reactions between these monothioxamines and diamines (1,2-diamino ethane and 1,3-diamino propane) were studied. Some new compounds wer... In this paper, six N,N'-disubstituted aonothioxamides were synthesized and the reactions between these monothioxamines and diamines (1,2-diamino ethane and 1,3-diamino propane) were studied. Some new compounds were synthesized by using these reactions. 展开更多
关键词 OU DISUBSTITUTED MONOTHIOXAMIDE AND study OF THEIR REACTIONS WITH DIAMINES synthesis OF N N LR UC Za
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Study on the Total Synthesis of Hainanolide (Ⅱ)──An Unexpected Hydroperoxide Containing Tricyclic Skeleton
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作者 Lu Yan ZHANG Wen Qian YANG +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing,100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第1期15-16,共2页
An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed b... An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed. 展开更多
关键词 ppm An Unexpected Hydroperoxide Containing Tricyclic Skeleton study on the Total synthesis of Hainanolide
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STUDY ON AB-CROSSLINKED POLYMERS Ⅰ. THE SYNTHESIS AND MECHANICAL PROPERTIES OF AB-CROSSLINKED POLYMERS BASED. ON PU/PS
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作者 贾铭椿 姚树人 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第4期347-352,共6页
The AB-crosslinked polymers (i.e. ABCP) with polystyrene as chain A and vinyl group blocked prepolymers of polyurethanes (PU) as chain B were synthesized and studied. The results of dynamic mechanical spectrometry (DM... The AB-crosslinked polymers (i.e. ABCP) with polystyrene as chain A and vinyl group blocked prepolymers of polyurethanes (PU) as chain B were synthesized and studied. The results of dynamic mechanical spectrometry (DMS) show that the compatibility between the components A and B can be improved greatly through chemical crosslinking during the formation of ABCPs. This effect is especially pronounced when short chain prepolymers is chosen as one of the components. It is apparent that the degree of crosslinking between the two components plays a major role in determining their compatibility. Copolymerizafion of styrene with maleic anhydride in chain A can improve the compatibility and broaden the damping temperature range. Mechanical properties of the sythesized ABCPs were also studied. 展开更多
关键词 PU study ON AB-CROSSLINKED POLYMERS THE synthesis AND MECHANICAL PROPERTIES OF AB-CROSSLINKED POLYMERS BASED ON PU/PS AB
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SYNTHESIS OF MESO-TETRA (4-METHOXYPHENYL-3-SULFONATE) PORPHINE AND SPECTROPHOTOMETRIC STUDY OF COLOUR REACTION WITH COPPER
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作者 Yu Shou CHEN Hng Xing YU +2 位作者 Xiao Pin WANG Ze Xing HUANG Shu Qiong HE 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期855-858,共4页
In this paper meso-tetra (4-methoxyphenyl-3-sulpho) Porphine (TMPPS_4) was synthesized and its colour reaction with copper was studied. It was found to be a highly sensitive and highly selective reagent for the direct... In this paper meso-tetra (4-methoxyphenyl-3-sulpho) Porphine (TMPPS_4) was synthesized and its colour reaction with copper was studied. It was found to be a highly sensitive and highly selective reagent for the direct spectrophotometric determination of ultramicro amount of copper. The apparent molar absorptivity of the complex is 3.72×10~5L/mol·cm. Beer's law is obeyed for Cu(Ⅱ)of 0~1.4μg/10ml. The interference of 21 different ions and 6 kinds of salts were examined and found to be minimal. The complex formation of Cu(Ⅱ) with TMPPS_4 is generally slow at room temperature<<25℃>, but the reaction can be accelerated in the presence of NH_2OH·>HCl and completed within 5min. At PH 5.2 the Soret band of TMPPS_4 overlaps almost completetely with that of the complex. Therefore, the complex formation is taken to completion at this PH. Then the Soret band of TMPPS_4 shifted away from that of the complex by acidification. This simple and rapid method has been successfully applied to the direct determination of Cu in Al-alloys, industrial water, foods and human hair. 展开更多
关键词 METHOXYPHENYL-3-SULFONATE PORPHINE AND SPECTROPHOTOMETRIC study OF COLOUR REACTION WITH COPPER synthesis OF MESO-TETRA
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SYNTHESIS OF MeO-SiO_2:Eu^(3+),Bi^(3+)LUMINOPUORS BY THE SOL-GEL METHOD AND A STUDY OF THEIR LUMINESCENCE SPECTRA
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作者 Bin LI Changjun OU Yiguang TIAN Hong XIAO Guiqin ZHANG (Institute of Materials Science,Jilin University,Changchun 130023,China) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第2期167-168,共2页
The luminophors MeO-SiO_2:Eu^(3+),Bi^(3+)and MeO-SiO_2Bi^(3+)(Me=Mg.Sr)were synthesized at relatively lower temperature by the sol-gel method using the silica sol as a source of silica.The optimum composition and synt... The luminophors MeO-SiO_2:Eu^(3+),Bi^(3+)and MeO-SiO_2Bi^(3+)(Me=Mg.Sr)were synthesized at relatively lower temperature by the sol-gel method using the silica sol as a source of silica.The optimum composition and synthesis conditions were obtained by studying the excitation and emission spectra and the effects of energy transfer from the Bi^(3+)ions to the Eu^(3+)ions. 展开更多
关键词 synthesis OF MeO-SiO2 SOL LUMINOPUORS BY THE SOL-GEL METHOD AND A study OF THEIR LUMINESCENCE SPECTRA SIO BI
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STUDY ON THE SYNTHESIS OF TETRACYCLIC DITERPENOID 7 Preparation of the Key Intermediate 5 for the Synthesis of Grandiflorenic Acid and its Analogues
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作者 Yun Xing CHENG Wei Shan ZHOU Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第4期291-294,共4页
The key intermediate 5 for synthesis of the contragestationally active diterpenoid grandiflorenic acid(1)and its analogues 2 and 3 was prepared and an acetyl transposition reaction occurred in the SeO_2 oxida- tion of 8.
关键词 In study ON THE synthesis OF TETRACYCLIC DITERPENOID 7 Preparation of the Key Intermediate 5 for the synthesis of Grandiflorenic Acid and its Analogues
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STUDY ON SYNTHESIS,CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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作者 段治邦 金钟声 +1 位作者 胡宁海 倪嘉缵 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期81-86,共6页
In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystal... In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism. 展开更多
关键词 study ON synthesis CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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Study on Synthesis and Chiral Inversion of Substituted Oxazolines
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期144-144,共1页
关键词 study on synthesis and Chiral Inversion of Substituted Oxazolines
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Study on the Allosteric Modulators of Muscarinic M_2-Receptors Ⅱ: Synthesis of W84 Analogous with PiperazinylDithiocarbonate
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作者 RuntaoLi UlrikeHolzgrabe 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期451-451,共1页
关键词 study on the Allosteric Modulators of Muscarinic M2-Receptors synthesis of W84 Analogous with PiperazinylDithiocarbonate
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Study on the Allosteric Modulators of Muscarinic M_2-Receptors: Synthesis of Unsymmetrical Analogous of W84
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作者 RuntaoLi UlrikeHolzgrabe 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期450-450,共1页
关键词 study on the Allosteric Modulators of Muscarinic M2-Receptors synthesis of Unsymmetrical Analogous of W84
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