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1.
o-Dihyroxy-3-phenylchromenone derivatives, namely, 6,7-dihydroxy-3-(3′,4′-dimethoxyphenyl)chromenone and 6,7-dimethoxy-3-(3′,4′-dihydroxyphenyl)chromenone, were obtained from 2,4,5-trihydroxybenzaldehyde/3,4-dimethoxyphenylacetic acid and 2-hydroxy-4,5-dimethoxybenzaldehyde/3,4-dihydroxyphenylacetic acid, respectively, in the presence of acetic anhydride and sodium acetate under an inert atmosphere, after treatment with MeOH/HCl(aq). The chromenone-crown ethers were prepared from cyclic condensation of o-dihydroxy-3-phenylchromenones with poly(ethylene glycol) ditosylates in the presence of CH3CN/alkali metal carbonates. The chromatographically purified novel chromenone-crown ethers were identified by 1H NMR, MALDI-TOF mass spectrometry and elemental analysis. The fluorescence and UV–vis spectroscopic properties of the obtained chromenone-crown ethers and their complexes with Li+, Na+ and K+ perchlorate salts were estimated in acetonitrile. The quantum yields of novel chromenone-crown ethers were determined by the comparative method.

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2.
李德江  傅和青 《有机化学》2006,26(8):1140-1143
戊二酸(1)与3-芳基-4-氨基-5-巯基-1,2,4-三唑(2a2o)在相转移催化剂四丁基碘化铵和POCl3作用下, 高收率合成了一系列新的1,2-双[3-芳基-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑-6-基]丙烷(3a3o). 其结构经IR, 1H NMR, MS和元素分析确证.  相似文献   

3.
Abstract

The cyclopolymerizations of 1,2:5,6-dianhydro-3,4-di-O-pentyl-D-mannitol (1b) and 1,2:5,6-dianhydro-3,4-di-O-decyl-D-mannitol (1c) were carried out using BF3OEt2 and t-BuOK. All the resulting polymers consisted of cyclic constitutional units, i.e., the extent of cyclization was 100%. The polymer structures for the polymerization with t-BuOK were (1→6)-2,5-anhydro-3,4-di-O-pentyl-D-glucitol (2b) and (1→6)-2,5-anhydro-3,4-di-O-decyl-D-glucitol (2c), whereas those with BF3O-decyl2 comprised 2,5-anhydro-D-glucitols as major units along with other cyclic ones. These polymers were soluble in n-hexane, CHCl3, and THF, but insoluble in water, which differs from the amphiphilic solubility of (1→6)-2,5-anhydro-3,4-di-O-methyl-D-glucitol (2a). The cation-binding properties of 2b and 2c were examined using alkali-metal picrates in order to compare them with those of 2a. The extraction yields for each cation decreased in the order of 2c < 2b < 2a. Every polymer exhibited a similar cation-binding selectivity in the order Cs+ > Rb+ > K+ ? Na+ > Li+. The ratio of K+ and Na+, K+/Na+, was 4.6 for 2a, 5.1 for 2b, and 7.1 for 2c in the increasing order 2a < 2b > 2c.  相似文献   

4.
The binding properties of two phenylketones (2a and 3a) and two ethylesters (2b and {3b) derived from p-tert-butyldihomooxacalix[4]arene or from p-tert-butylcalix[4]arene, in the cone conformation, towards transition (Ag+, Ni2+, Cu2+, Co2+, Zn2+, Fe2+ and Mn2+) and heavy (Cd2+, Hg2+ and Pb2+) metal cations have been determined by extraction studies with metal picrates and liquid membrane transport experiments with the same salts. The affinity of these ligands for Ag+ has also been investigated by 1H NMR spectroscopy. Both ketones are better extractants than the esters, and show a strong preference for Ag+, while Cu2+ is the most extracted cation with the esters. 1H NMR titrations with AgSO3CF3 indicate 1 : 1 complexes for all ligands, those with ketones are more stable, on the NMR time scale, than those with esters. Both esters are good carriers for Ag+, and 2b exhibits the highest transport rate (4.7 mol h-1) found until now with dihomooxacalix[4]arene derivatives.  相似文献   

5.
ABSTRACT

Starting from 3,4-di-O-acetyl-L-rhamnal (6) and thymine (7) the unsaturated nucleosides 1-(2′,3′,6′-trideoxy-4′-O-acetyl-α- and β-L-erythro-hex-2′-enopyranosyl)-thymine (8a and 8b) were prepared in anomerically pure form. In solution 8a was shown to be present in the 5 H o and 0 H 5 conformations, whereas the predominant conformation of 8b was 5 H o. Chemical transformation of 8a and 8b led to the saturated nucleosides 1-(2′,3′,6′-trideoxy-α- and β-L-erythro-hexopyranosyl)thymine (10a and 10b, respectively), which were converted into 1-(4′-azido-2′,3′,4′,6′-tetradeoxy-α- and β-L-threo-hexopyranosyl)thymine (12a and 12b). Preliminary biological studies showed that 9b was inactive against the HIV-1 and HIV-2 viruses.  相似文献   

6.
The presented ethylenedioxy compounds5a,5d,6a and6c are examples of novel cyclic ethers, while macrocyclic polyethers represent new crown ether analogues. New coumestan-crowns5a-f, derivatives of 6,7-dihydroxy-3,4-dihydro-2H-dibenzofuran-1-one and 6,7-dihydroxy-3,3-dimethyl-3,4-dihydro-2H-dibenzofuran-1-one6a-e were synthesized from the correspondingo-dihydroxy compounds3a-b,4a-b and ditosylates or dichlorides of di- or triethylene glycol in the presence of K2CO3, in DMF/H2O (15/1) solutions at 65–75 °C for 35 hours. The structure of the macrocyclic ethers obtained were confirmed by1H-NMR,13C-NMR, IR spectra and elemental analyses.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.  相似文献   

7.
设计合成了四种三苯基咪唑类化合物:4,5-二苯基-2-对甲酰基苯基咪唑(2a),4,5-二(2-硝基苯基)-2-对甲酰基苯基咪唑(2b),N-苄基-4,5-二苯基-2-对甲酰基苯基咪唑(2c)和N-苄基-4,5-二(2-硝基苯基)-2-对甲酰基苯基咪唑(2d),并用FT-IR,NMR和MS进行结构表征.在乙酸乙酯-石油醚溶液中获得了2c的单晶,用X射线单晶衍射法测定了其晶体结构,晶体属于三斜晶系,空间群P1,晶胞参数a=0.73796(15)nm,b=0.90136(18)nm,c=1.6644(3)nm,α=86.87(3)°,β=78.25(3)°,γ=89.94(3)°,V=1.0822(4)nm3,Dc=1.272g/cm3,Z=2,F(000)=436,μ=0.077mm-1,R1=0.0459,wR2=0.1303.研究了四种化合物的紫外与荧光性质,发现官能团硝基与苄基的引入,对其吸收峰和发射峰均有不同程度的影响:在紫外光谱中两种官能团均使吸收峰蓝移;在荧光光谱中苄基使发射峰蓝移而硝基使发射峰红移.测定了2a和2c在不同溶剂中的荧光寿命,其中2a在DMSO中寿命最长,为3.18ns.这些光谱性质为研究其双光子吸收、双光子荧光和非线性光学性质奠定了理论和实验基础.  相似文献   

8.
利用三有机锡氢氧化物和手性配体(4R)-3-[[(2S)-5-氧-2-吡咯烷基]羰基]-4-噻唑烷甲酸(HL)反应合成了3个三有机锡(4R)-3-[[(2S)-5-氧-2-吡咯烷基]羰基]-4-噻唑烷甲酸酯R3SnL[1,R=c-C6H11(a),C6H5(b),C6H5C(CH3)2CH2(c)],通过元素分析、IR、1H NMR和X-射线单晶衍射表征了其结构。化合物1a属正交晶系,P212121空间群;化合物1b属单斜晶系,P21空间群。二者均为由羧基氧和内酰胺羰基氧桥联配位形成的右螺旋链状有机锡配位聚合物,锡原子具有五配位[SnC3O2]畸变三角双锥构型。化合物1a和1b对体外2种人癌细胞Colo205和Bcap37增殖均有强的抑制作用,其活性为1b1a。  相似文献   

9.
The reaction of OsCl2(PPh3)3 with [nido-7-R1-8-R2-C2B9H10]K+ produced a series of new exo-nido-osmacarborane complexes exo-nido-5,6,10-[Cl(Ph3P)2Os]-5,6,10-(-H)3-10-H-7-R1-8-R2-7,8-C2B9H6 (1: R1 = R2 = H; 2: R1 = R2 = Me; 3: R1 = R2 = PhCH2; 4: R1 + R2 = 1,2-C6H4(CH2)2; 5: R1 = H, R2 = Me) in which the osmium-containing group is linked to the nido-carborane ligand through three two-electron three-center bonds. Compounds 15 are formed as mixtures of symmetric (a) and asymmetric (b) isomers; pure symmetric isomers 2a and 4a were isolated by fractional crystallization, and the mixture of isomers 3a, was quantitatively separated into individual compounds 3a and 3b by column chromatography on silica gel. Detailed analysis of the 31P{1H}, 1H, 11B NMR spectra of 1a,b5a,b and 2D 1H-1H{11B} and 11B{1H}-11B{1H} NMR spectra of 3a and 3b was performed. The structures of isomers 2a and 4a were confirmed by an X-ray diffraction study. According to the NMR and X-ray diffraction data, the isomerism of exo-nido-complexes 1a,b5a,b is actually the cistrans-isomerism of ligand arrangement in the octahedral coordination of the Os atom.  相似文献   

10.
利用三有机锡氢氧化物和手性配体(4R)-3-[[(2S)-5-氧-2-吡咯烷基]羰基]-4-噻唑烷甲酸(HL)反应合成了3个三有机锡(4R)-3-[[(2S)-5-氧-2-吡咯烷基]羰基]-4-噻唑烷甲酸酯R3SnL[1,R=c-C6H11a),C6H5b),C6H5C(CH32CH2c)],通过元素分析、IR、1H NMR和X-射线单晶衍射表征了其结构。化合物1a属正交晶系,P212121空间群;化合物1b属单斜晶系,P21空间群。二者均为由羧基氧和内酰胺羰基氧桥联配位形成的右螺旋链状有机锡配位聚合物,锡原子具有五配位[SnC3O2]畸变三角双锥构型。化合物1a1b对体外2种人癌细胞Colo205和Bcap37增殖均有强的抑制作用,其活性为1b >1a。  相似文献   

11.
系列单取代烷氧基-2-羟丙基-β-环糊精的合成与表征   总被引:1,自引:0,他引:1  
以环氧氯丙烷和脂肪醇为原料, 通过相转移催化法合成了乙基、正丙基、正丁基和正戊基缩水甘油醚(14), 并利用所合成的缩水甘油醚和β-环糊精为原料, 分别在弱碱水溶液(1.5%)和强碱水溶液(30%)中制备并用硅胶柱分离出单2位取代的乙氧基、丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(1a4a)和单6位取代的丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(2b4b), 利用薄层色谱、红外光谱、差热扫描量热分析、质谱和核磁共振等手段对所合成的产品进行了表征.  相似文献   

12.
The reaction of DL-malic and succinic acids with thiocarbohydrazide afforded 1,2-bis[4-amino-5-mercapto-1,2,4-triazol-3-yl]-ethane derivatives 3a and 3b. The reaction of 3a,b with phenacyl bromide and benzoin afforded 1,2-bis-1,2,4-triazolo [3,4-b][1,3,4]thiadiazine derivatives 4 and 5. The carboethoxymethylation of 3a and 3b gave 6a and 6b, respectively, and their reactions with carbon disulfide and benzoylisothiocyanate gave the 1,2-bis-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole 7 and 9, and with p-nitrobenzaldehyde gave a Schiff's base and dihydrothiadiazole 8. The structures were confirmed by using 1 H and 13 C NMR spectra. Selected members of these compounds were screened for antimicrobial activity.  相似文献   

13.
The crystal structures of two 12-membered crown ethers, benzo-12-crown-4 (1) and naphtho-12-crown-4 (2), have been determined by X-ray analysis. Both structures are molecular. Compound1 is monoclonic,P21/b,a=8.466(3),b=8.019(3),c=33.590(10) Å, =90.99(3)o. The unit cell contains two crystallographically independent molecules of1 with similar conformations. Compound2 is also monoclinic,P21/a,a=24.148(8),b=14.535(4),c=7.987(5) Å, =102.87(2)o. Two independent molecules in the unit cell have significantly different conformations. Supplementary data relating to this publication have been deposited with the British Library as Supplementary Publication No. SUP 82145 (19 pages).  相似文献   

14.
Diacetylplatinum(II) complexes [Pt(COMe)2(N^N)] (N^N = bpy, 3a; 4,4′-t-Bu2-bpy, 3b) were found to undergo oxidative addition reactions with organyl halides. The reaction of 3a with methyl iodide and propargyl bromide led to the formation of the cis addition products (OC-6-34)-[Pt(COMe)2(R)X(bpy)] (R = Me, X = I, 4a; CH2C≡CH, X = Br, 4k). Analogous reactions of 3a with ethyl iodide, benzyl bromide, and substituted benzyl bromides, 3-(bromomethyl)pyridine, 2-(bromomethyl)thiophene, allyl bromide, and cyclohex-2-enyl bromide led to exclusive formation of the trans addition products (OC-6-43)-[Pt(COMe)2(R)X(bpy)] (X = I, R = Et, 4b; X = Br, R = CH2C6H5, 4c; CH2C6H4(o-Br), 4d; CH2C6H4(p-COOH), 4e; CH2-3-py (3-pyridylmethyl), 4f; CH2-2-tp (2-thiophenylmethyl), 4g; CH2CH=CH2, 4h; c-hex-2-enyl (cyclohex-2-enyl), 4i). All complexes 4 were characterized by microanalysis, 1H and 13C NMR and IR spectroscopy. Additionally, complexes 4a, 4f, and 4g were characterized by single-crystal X-ray diffraction analyses. Reactions of 3a and 3b with o-, m- and p-bis(bromomethyl)benzene, respectively, led to the formation of dinuclear platinum(IV) complexes [{Pt(COMe)2Br(N^N)}2-{μ-(CH2)2C6H4}] (5). These complexes were characterized by microanalysis, IR spectroscopy, and depending on their solubility by 1H and 13C NMR spectroscopy, too. A single-crystal X-ray diffraction analysis of complex [{Pt(COMe)2Br(bpy)}2{μ-m-(CH2)2C6H4}] (5b) confirmed its dinuclear composition. The solid-state structures of 4a, 4f, 4g, and 5b are discussed in terms of C–H···O and O–H···O hydrogen bonds as well as π–π stacking between aromatic rings.  相似文献   

15.
A series of double-armed benzo-15-crown-5 lariats (3–8) have been synthesized by the reaction of 4′, 5′-bis(bromomethyl)-benzo-15-crown-5 (2) with 4-hydroxybenzaldehyde, phenol, 4-chlorophenol, 4-methoxyphenol, 2-hydroxybenzaldehyde, and 4-acetamidophenol in 43 ~ 82% yields, respectively. The complex stability constants (K S) and thermodynamic parameters for the stoichiometric 1:1 and/or 1:2 complexes of benzo-15-crown-5 1 and double-armed crown ethers 3–8 with alkali cations (Na+, K+, Rb+) have been determined in methanol–water (V/V=8:2) at 25 °C by means of microcalorimetric titrations. As compared with the parent benzo-15-crown-5 1, double-armed crown ethers 3–8 show unremarkable changes in the complex stability constants upon complexation with Na+, but present significantly enhanced binding ability toward cations larger than the crown cavity by the secondly sandwich complexation. Thermodynamically, the sandwich complexations of crown ethers 3-8 with cations are mostly enthalpy-driven processes accompanied with a moderate entropy loss. The binding ability and selectivity of cations by the double-armed crown ethers are discussed from the viewpoints of the electron density, additional binding site, softness, spatial arrangement, and especially the cooperative binding of two crown ether molecules toward one metal ion.  相似文献   

16.
Two new 3,5-diaryl-1H-pyrazoles: 3(5)-(4-tert-butylphenyl)-5(3)-(naphthalene-2-yl)-1H-pyrazole (1) and 5-(4-(benzyloxy)phenyl)-3-(furan-2-yl)-1H-pyrazole (2) were synthesized and characterized. Two strong ions peaks [2M]+ and [2M + Na]+ observed in the ESI–MS spectra are attributed to the dimerization process in solution formed by intermolecular N–H···N hydrogen bonds. The crystal structures have been determined by X-ray crystal structure analysis. Compound 1 exists as a pair of tautomers 1a and 1b, and its dimer [R 22(6) motif] is formed by the tautomers 1a and 1b. Compound 2 only exists as a 2a tautomer, and interesting intermolecular N–H···O and O–H···N hydrogen bonds link two pyrazoles and two methanol molecules, leading to the formation of an R 44(10) dimer motif.  相似文献   

17.
2-Chlorophenyl methanethiol undergoes air oxidation catalyzed by different selenides and yields the corresponding disulfide 1 in two polymorphic forms, 1a and 1b. In the molecular structures of the two new polymorphs of o,o′-dichloro dibenzyl disulfide, the dihedral angles between the dibenzyl groups are 82.0(1)°, (1a), and 73.7(4)°, (1b), respectively [(1a): P-1, a = 8.424(2) Å, b = 8.838(2) Å, c = 10.5823(19) Å, α = 90.122(18)°, β = 112.19(2)°, γ = 95.19(2)°, V = 725.9(3) Å3; (1b): P21/n, a = 10.5888(10) Å, b = 9.1590(6) Å, c = 15.2489(14) Å, β = 103.072(9)°, V = 1440.6(2) Å3]. MOPAC computational studies yield dihedral angles of 89.6(5)° and 71.9(9)°. Crystal packing is stabilized by weak π-ring (C?H···Cg) intermolecular interactions in both 1a and 1b and by additional weak Cg ··· Cg intermolecular interactions in 1b, which influence the bond distances, bond angles, and torsion angles of the dibenzyl groups in each polymorph. Additional characterization of each polymorph has been carried out by TEM, IR, 1H and 13C NMR spectroscopy, microanalysis, and by FAB mass spectrometry. TEM studies of a sample of 1a show that it contains cigar-shaped crystallites.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

18.
史合方  曹玲华 《有机化学》2005,25(9):1066-1070
2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖基异硫氰酸酯(1)与2-氨基-4-取代苯基噻唑(2a2b)反应, 生成糖基硫脲衍生物3a3b, 再在伯胺存在下经氯化汞脱硫, 得到一系列新的N-烷基/芳基-N'-(4-芳基噻唑-2-基)-N"-糖基胍类化合物(4a4e, 5a5e). 所有新化合物的结构均经IR, 1H NMR, MS谱和元素分析证实, 所得产物均为β-构型. 生物活性测试结果表明, 化合物4b5d对HIV-1 PR表现出了较高的抑制活性.  相似文献   

19.
The ortho-metalated complex [Pd(x){κ 2 (C,N)-[C6H4CH2NRR′ (Y)}] (2a4a and 2b3b) was prepared by refluxing in benzene equimolecular amounts of Pd(OAc)2 and secondary benzylamine [a, EtNHCH2Ph; b, t-BuNHCH2Ph followed by addition of excess NaCl. The reaction of the complexes [Pd(x){κ 2 (C,N)-[C6H4CH2NRR′ (Y)}] (2a4a and 2b3b) with a stoichiometric amount of Ph3P=C(H)COC6H4-4-Z (Z = Br, Ph) (ZBPPY) (1:1 molar ratio), in THF at low temperature, gives the cationic derivatives [Pd(OC(Z-4-C6H4C=CHPPh3){κ 2 (C,N)-[C6H4CH2NRR′(Y)}] (5a9a, 4b6b, and 4b′6b′), in which the ylide ligand is O-coordinated to the Pd(II) center and trans to the ortho-metalated C(6)H(4) group, in an “end-on carbonyl”. Ortho-metallation, ylide O-coordination, and C-coordination in complexes (5a9a, 4b6b, and 4b′6b′) were characterized by elemental analysis as well as various spectroscopic techniques.  相似文献   

20.
A series of novel helicid derivatives containing 3,4-dihydropyrimidin-2(1H)-one and 3,4-dihydropyrimidine2(1H)-thione moiety (3a–3f and 4a–4f) were synthesized starting from helicid. The structure of the new compounds were characterized by 1H NMR, IR and HR-MS spectra. The sedative-hypnotic activities of the target compounds were evaluated using the test of spontaneous locomotor activity in mice. All of the derivatives produced moderate to high activities; in particular, compound 4a presented the most potent sedative-hypnotic effect in comparison to the other derivatives, and derivatives 3a, 3c, 3d, 3e and 3f also showed potent activities.  相似文献   

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