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1.
Synthesis of the optically active metabolite of clausenamide cm2(3,5-dihydroxy-5-(α-hydroxylbenzyl)-1-methyl-4-benzylpyrrolidin-2-one)from 3-O-acetyl-clausenamide was described.  相似文献   

2.
The structures of five metabolites (2-6) of agarofuran 1 were confirmed by synthesis. The configuration of the secondary hydroxyl in 7 was determined by Horeau′s method. The configuration of C-2 in compound 4 and 5 was determined by their stereochemistry and NMR.  相似文献   

3.
A new colorimetric recognition receptor 1 based on the dual capability containing NH binding sites of selectively sensing anionic guest species has been synthesized. Compared with other halide anions, its UV/Vis absorption spectrum in dimethyl sulfoxide showed the response toward the presence of fluoride anion with high selectivity, and also displayed dramatic color changes from colorless to yellow in the presence of TBAF (5 × 10^-5 mol/L). The similar UV/Vis absorption spectrum change also occurred when 1 was treated with AcO^- while a little change with H2PO^-4 and OH^-. Receptor 1 has almost not affinity abilities to Cl^-, Br^- and I^-. The binding ability of receptor 1 to fluoride with high selectivity over other halides contributes to the anion size and the ability of forming hydrogen bonding. While the different ability of binding with geometrically triangular (AcO^-), tetrahedral (H2PO^-4 ) and linear (OH^-) anions maybe result from their geometry configuration.  相似文献   

4.
胡红民  俞建长 《结构化学》2010,29(3):407-413
In this paper,La(3)-doped Nano-TiO2(La(3)-TiO2) was synthesized via hydrothermal process.Structure and optical properties of the synthesized samples were characterized via XRD,FT-IR,DRS,etc.The results showed that the phase transformation of TiO2 from anatase to rutile was effectively prevented by La(3)-doping,which improved the thermal stability of anatase,and also suppressed particle aggregation and grain growth of TiO2.The formation of Ti-O-La bond promoted UV absorption intensity of TiO2,and provoked red shift of absorbed light.And the spectra response range of TiO2 was extended significantly to visible light by La(3)-doping,then photocatalytic performance was improved effectively.Compared with pure nano-TiO2,the performance of La(3)-TiO2 which photocatalyticly degraded methyl orange was increased significantly.  相似文献   

5.
The synthesis of N-substituted p-hydroxybenzoic amides using a liquid phase approach is described. Poly(ethylene glycol)(PEG) and p-hydroxybenzoic acid were linked by oxalyl chloride to give compound 1, which was chlorinated by thionyl chloride, followed by amidation with NHR^1R^2 to yield compound 3. Hydrolysis of compound 3 gave the title amide 4.These crude library members were obtained in good yields with high purities.  相似文献   

6.
JinWANG  FeiLiTANG 《中国化学快报》2002,13(11):1055-1056
A novel distamycin analogue was synthesized by chloroform reaction and DCC/HOBT coupling reaction without using amino protection and deprotection.  相似文献   

7.
陈华梅  王月红  林海  林华宽 《结构化学》2007,26(9):1027-1032
The title compound, 1,2-bis-(p-nitro-phenylsulfonamido)-4,5-dinitrobenzene, was synthesized and characterized by elemental analysis, IR and 1H NMR. A pale yellow prism crystal of C23H26N8O13S2 (Mr = 686.64) was obtained in DMF solution and determined by single-crystal X-ray diffraction method. It crystallizes in triclinic system, space group P1 with a = 10.346(4), b = 12.210(5), c = 12.976(5) , α = 108.220(8), β = 99.482(4), γ = 95.490(4)°, V = 1516.7(10) 3, Z = 2, Dc = 1.504 g/cm3, F(000) = 712, μ = 0.254, Mr = 686.64, the final R = 0.0561 and wR = 0.1487. One sulfonamido group of the title compound is deprotoned and forms N(3)=C(13). The crystal involves N,N-dimethylamine from the decomposition of DMF and the proton is transferred to N,N- dimethylamine. It is a strong proof for the characterization of deprotoned recognition compound by X-ray single-crystal structure.  相似文献   

8.
β-D-Glcp-(1→)3-[β-D-Glcp-(1→6)-]α-D-Manp-(1→3)-β-D-Glcp-(1→3)-[β-D-Glcp(1→6)-]D-Glcp(18)and β-D-Glcp(1→3)-[β-D-Glcp(1→6)-]α-D-Manp-(1→3)-β-D-Glcp(1→3)-[β-D-Glcp(1→6)-]β-D-Glcp-D-(1→3)-Glcp-1→OM3(29)were synthesized as the analogues of the immunomodulator β-D-Glcp-(1→3)-[β-D-Glcp(1→6)-]α-D-Glcp(1→3)-β-D-Glcp(1→63)-[β-D-Glcp(1→6)-]D-Glcp through coupling of trisaccharide donors 9 with trisaccharide acceptor 16 and tetrasaccharide acceptor 27 followed by deprotection,respectively.  相似文献   

9.
The title compound, 1-(N,N-di-(p-toluenesulfonyl))-amino-2-(N'-p-toluenesulfonyl)-amino-3,5-dinitrobenzene, was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in orthorhombic, space group Pna21 with a = 13.723(2), b =25.354(4), c = 8.6565(12)(A), V= 3011.9(8)(A)3, Z= 4, Mr = 660.68, F(000) = 1368, Dc = 1.457 g/cm3,μ = 0.309, the final R = 0.0609 and wR = 0.1042. The H atom of N2-H group, which is the unique recognition site to anion, is enveloped by two oxygen atoms and one benzene from two and one p-toluenesulfonyl moieties, respectively.  相似文献   

10.
StudyontheTotalSynthesisofHainanolide-ConstructionofTricyclicIntermediate(I)LuYanZHANG;ShiZhiCHEN;DongWEI;LiangHUANG;JiJieCHA...  相似文献   

11.
Most of natural and synthetic compounds1-3 with benzofuran moieties exhibit broad spectrum bioactivities, such as antitumor, antifungal, antivirus activities; 5-lipoxygensase inhibitory activity and 5α-reductase inhibitory activity4-7. Moreover, they are also key intermediates for constructing some natural bioactive quinones8.As part of our research program focused on novel ortho-naphthofuranoquinone derivatives, various 3-substituted benzofurans were required as synthetic intermediates. Synt…  相似文献   

12.
A total synthesis of (±)-iridolactone ( 1 ) from bicyclo[2.2.1]ketone 6 is described. Trisubstituted cyclopentenoid aldehyde 7 is a key intermediate.  相似文献   

13.
以无机试剂组成的三元复合亚硝解脱苄试剂, 由四乙酰基二苄基六氮杂异伍兹烷(TADBIW)合成了四乙酰基二亚硝基六氮杂异伍兹烷(TADNIW•H2O)——合成高能量密度化合物六硝基六氮杂异伍兹烷(HNIW)和其他高能量密度精细化工产品的另一重要前体. 目标化合物的分子结构用1H NMR, IR, MS及元素分析方法进行结构鉴定. 在乙酸乙酯、丙酮和DMF组成的混合溶剂中制得TADNIW•H2O单晶, 用X射线衍射法测定了目标化合物的晶体结构, 晶体学数据: 单斜晶系, 空间群P21/n; 晶胞参数: a=1.0738(2) nm, b=1.4870(3) nm, c=1.1185(2) nm, =98.95(3)°; V=1.7642(6) nm3; Z=4; Dc=1.553 g•cm-3, F(000)=864, =0.126 mm-1. 与其他前体相比, TADNIW更容易经硝解转化为HNIW.  相似文献   

14.
1-Adamantyl bromomethyl ketone and 1-adamantylmethyl chloromethyl ketone react with potassium thiocyanate in dimethylformamide to give the corresponding thiocyanatoketones which cyclize under the influence of HCl into 4-(1-adamantyl) and 4(-adamantylmethyl)chlorothiazole respectively. 4-(1-Adamantyl)-2-amino-5-bromothiazole and its N-derivative were synthesized by the reaction of 1-adamantyl dibromomethyl ketone with thioureas and N-substituted thiourea in acetonitrile.  相似文献   

15.
Methods for the synthesis of N-cyanoimines in the period between 1959 and 2003 and their chemical properties are examined. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–973, July, 2005.  相似文献   

16.
以D-(+)-葡萄糖酸内酯为原料,经三甲硅基保护羟基后与5-溴-2-氯-4′-乙氧基二苯甲烷偶联制得(2S,3R,4S,5S,6R)-2-[4-氯-3-(4-乙氧苄基)苯基]-6-(羟甲基)-2-甲氧基四氢-2H-吡喃-3,4,5-三醇(2); 2经羟基保护、氧化和羟醛缩合等5步反应制得(3S,4S,5R,6S)-3,4,5-三(苄氧基)-6-[4-氯-3-(4-乙氧苄基)苯基]-2-(羟甲基)-6-甲氧基四氢-2H-吡喃-2-甲醛(7); 7经还原、脱苄同时关环制得埃格列净(1S,2S,3S,4R,5S)-5-[4-氯-3-(4-乙氧苄基)苯基]-1-(羟甲基)-6,8-二氧杂二环[3.2.1]辛烷-2,3,4-三醇,其结构经1H NMR和LC-MS表征。  相似文献   

17.
Xiaoxia Zhang 《Tetrahedron》2010,66(6):1177-5455
A wide variety of substituted quinolines are readily synthesized under mild reaction conditions by the 6-endo-dig electrophilic cyclization of N-(2-alkynyl)anilines by ICl, I2, Br2, PhSeBr, and p-O2NC6H4SCl. The reaction affords 3-halogen-, selenium- and sulfur-containing quinolines in moderate to good yields in the presence of various functional groups. Analogous quinolines bearing a hydrogen in the 3-position have been synthesized by the Hg(OTf)2-catalyzed ring closure of these same alkynylanilines.  相似文献   

18.
A non-oxidant and metal-free strategy for synthesizing iso-coumarin by using a continuous electrochemical microreactor to initiate an oxidative cyclization reaction of o-(1-alkynyl) benzoate and radicals. This efficient and clean continuous electrosynthesis method not only avoids the complicated gas protection operation and production of by-products in the batch processes, but also help to overcome the difficulty that batch metal catalysis and electrocatalysis are difficult to scale up, and has the potential for pilot-scale experiment.  相似文献   

19.
Interaction of potassium salts of quinazolin-2-thiol-4-one with -substituted allyl halides gave thiazoloquinazolinones with linear or angular structures depending on the structure of the carbonyl radical. S-Allyl substituted quinazolin-2-thiol-4-one reacted with halogens to give iminium salts of thiazinoquinazolinone with an angular structure. The conversion of these salts to the corresponding bases and thiazoloquinazolinones has been studied.  相似文献   

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