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1.
3-吡啶基醚类化合物的分子全息QSAR研究   总被引:2,自引:0,他引:2  
李华  张华北 《化学学报》2005,63(11):1018-1022
采用分子全息定量构效关系(HQSAR, hologram quantitative structure-activity relationship)方法, 研究了28个3-吡啶基醚类化合物对乙酰胆碱α4β2受体的亲和性与它们的分子结构之间的关系, 讨论了分子碎片大小、分子碎片亚结构类型以及分子全息长度对QSAR的影响, 得到了较好的HQSAR模型, 模型的交叉验证系数平方q2=0.670, 非交叉相关系数平方r2=0.965, 偏差S=0.093. 利用HQSAR的颜色编码, 对化合物中不同基团对亲和活性的影响进行了讨论, 对新配体的合成具有一定的指导作用.  相似文献   

2.
In search of environmentally benign insecticides with high activity, low toxicity, and low residue, a series of novel anthranilic diamide containing propargyl ether were designed and synthesized. All compounds were characterized by 1H NMR spectroscopy, high‐resolution mass spectrometry, or elemental analysis. The single crystal structure of 18g was determined by X‐ray diffraction. The insecticidal activities against Lepidoptera pests of the new compounds were evaluated. Their insecticidal activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella) indicated that most of the compounds showed moderate to high activities at the tested concentration.  相似文献   

3.
Three new phenyl ether derivatives, 3‐hydroxy‐5‐(3‐hydroxy‐5‐methylphenoxy)benzoic acid ( 1 ), 3,4‐dihydroxy‐5‐(3‐hydroxy‐5‐methylphenoxy)benzoic acid ( 2 ), 3‐[3‐hydroxy‐5‐(hydroxymethyl)phenoxy]‐5‐methylphenol ( 3 ), and three known compounds 4 – 6 were obtained from the fermentation broth of Aspergillus carneus HQ889708, which was isolated from sea water from South China Sea. The structures of compounds 1 – 3 were established on the basis of spectroscopic methods including ESI‐MS and NMR. Compounds 4 – 6 were reported before as synthesized products, herein, they are reported from nature for the first time.  相似文献   

4.
A concise synthesis of the enantiomeric forms of wine lactone ( 5 ), epi‐wine lactone ( 14 ), dill ether ( 6 ), and epi‐dill ether ( 15 ) was accomplished starting from the enantiomeric forms of p‐mentha‐1,8(10)‐diene‐3,9‐diol ( 8 ) (Scheme 3). The latter compounds were previously prepared in high optical purity by means of lipase‐mediated kinetic resolution, and they were the common building blocks for this divergent synthesis. The key steps were a number of chemo‐ and diastereoselective reactions of which the oxidation of 8 to the lactone 7 (see Table 1), the diastereoselective reduction of 7 to the lactones 14 and 5 (see Table 2), and the reduction of enol‐ether 16 to ether 15 were studied comprehensively. The effectiveness of this new synthetic approach allows the preparation of the title p‐menthane monoterpenes, which are of considerable interest to the perfume industry, in high yield and in a few simple experimental steps.  相似文献   

5.
Strobilurins are a class of important agricultural fungicides that are used widely in plant protection. To find new strobilurin analogues with high activity against resistant pathogens, a series of new strobilurin derivatives bearing 1,2,4‐triazole oxime ether side chain 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h were designed and synthesized. Their structures were confirmed by IR, 1H NMR, EIMS, and elemental analyses. Bioassays indicated that some of the compounds showed good fungicidal activities in the concentration of 50 mg/L. For example, compound 3f possessed 100%, 100%, and 95.5% inhibition against Fusarium omysporum, Physalospora piricola Nose, and Gibberella saubinetii at the concentration of 50 mg/L, respectively.  相似文献   

6.
Previous applications of the Flory–Patterson theory in the analysis of the excess molar enthalpies at 25°C for some binary mixtures composed of ethers, n-alkanes, br-alknes, and cycloalkanes are reviewed. The possibility of correlating the Flory interaction parameters X ij in terms of the acentric factors of the components is examined. For selected ether (1) + n-alkane(2) mixtures, a set of linear relations between X 12 and the acentric factors of the n-alkanes are reported.Visiting Professor on sabbatical leave from the  相似文献   

7.
N‐Boc‐protected L ‐proline ( 6 ) was converted into the bicyclic lactim ether (8aS)‐6,7,8,8a‐tetrahydro‐1‐methoxypyrrolo[1,2‐a]pyrazin‐4(3H)‐one ( 5 ) in four steps (Scheme 1). Deprotonation with LDA or LHMDS and subsequent alkylation resulted in the diastereoisomeric products cis‐ and trans‐ 9 . The diastereoselectivity was mainly dependent on the electrophile. Whereas small alkyl halides gave preferably cis‐ 9 , sterically more‐demanding alkyl halides resulted in cis/trans mixtures. Electrophiles bearing a π‐system favored the trans‐products 9 . Some isolated cis‐ and trans‐lactim ethers 9 were converted to the corresponding diketopiperazines cis‐ and trans‐ 10 by acid hydrolysis. The structures and configurations of several compounds were confirmed by NMR and NOE experiments, as well as by X‐ray crystallography (Figs. 1–4).  相似文献   

8.
The synthesis, preliminary in vivo biological activity, singlet oxygen and fluorescence yields of a series of alkyl ether derivatives of chlorophyll-a analogs are described. For short-chain carbon ethers (1–7carbon units), it was observed that the biological activity increased by increasing the length of the carbon chain, being maximum in compounds with n-hexyl and n-heptyl chains. Related sensitizers prepared by reacting 2-(1-bromoethyl)-2-devinylpyropheophorbide-a with (sec)alcohols were found to be less effective. Under similar treatment conditions, photosensitizers containing cis- and trans- 3-hexenyl side chains were ineffective. Thus, both stereochemical and steric factors caused differences in sensitizing activity. In general, pyropheophorbide-a analogs were found to be more active than related chlorin e6 derivatives, in which the isocyclic ring (ring “E”) was cleaved. Related photosensitizers in the 9-deoxy- series were found to be as effective as the corresponding pyropheophorbide-a analogs. The photosensitizers prepared from pyropheophorbide-a methyl ester and chlorin e6 trimethyl ester have long wavelength absorption at 660 nm (ε 45000 to 50000). Reduction of the carbonyl group in the pyropheophorbide-a to methylene (ring E) resulted in a blue shift to 648 nm (ε 38000).  相似文献   

9.
A practical, two‐step synthesis of crown ether functionalized pyrimidines has been developed. The reaction conditions have been optimized, and the protocol is generalized for series of substrates. These newly synthesized compounds exhibited antimicrobial activity against bacterial strains Staphylcoccus aureus (Gram‐positive) and Escherichia coli (Gram‐negative). These compounds were also found to be potent antifungal agents Aspergillus niger and Candida albicans strains, respectively.  相似文献   

10.
Synthesis of deaminocolchinyl methyl ether 9 was achieved from tetramethoxy-substituted biphenyl-2-carb-aldehyde 12 via tricyclic ketone 20 and 5,6-didehydro congener 11 . Compound 9 was identical in every respect with material prepared from colchicine via 6,7-didehydro congener 10 . Measuring inhibition of tubulin polymerization in vitro showed compounds 4 , 5 , and 9 – 11 of the alloseries of colchicinoids to be particularly potent inhibitors.  相似文献   

11.
When heated with sodium ethoxide in ethanol 7-methylidenebicyclo[3.3.1]nonan-3-endo-ol (endo- 1 ) is converted into 1-methyl-2-oxa-adamantane ( 3 ). This reaction involves nucleophilic addition of a hydroxy group to an unactivated olefinic bond. Formation of the cyclic ether 3 also takes place when endo- 1 is heated in aqueous ethanol. This electrophilic addition is strongly catalysed by weak acids and suppressed by weak bases. These unusual reactions proceed more slowly with 7-methylbicyclo[3.3.1]non-6-en-3-endo-ol (endo- 2 ) and can be ascribed to a proximity effect. This follows from the IR . and NMR . spectra of endo- 1 and endo- 2 which show strong intramolecular hydrogen (OH-π) bonding. The unsaturated endo- and exo-alcohols 1 and 2 , respectively, undergo only exo-complexation with silver ion.  相似文献   

12.
The development of polymers with on-demand degradability is required to alleviate the current global issues on polymer-waste pollution. Therefore, we designed a vinyl ether monomer with an o-nitrobenzyl (oNBn) group as a photo-deprotectable pendant (oNBnVE) and synthesized an alternating copolymer with an oNBn-capped acetal backbone via cationic copolymerization with p-tolualdehyde (pMeBzA). The resultant alternating copolymer could be rapidly degraded into lower-molecular-weight compounds upon simple exposure to UV irradiation without any reactants or catalysts, while it was sufficiently stable toward heat and ambient light. This degradation proceeds via cleavage of the hemiacetal structure generated upon photo-deprotection of the oNBn pendant. The oNBn-peculiar degradability allowed the exclusive photo-degradation of the oNBnVE/pMeBzA segments in a diblock copolymer composed of oNBnVE/pMeBzA and benzyl vinyl ether (BnVE)/pMeBzA segments.  相似文献   

13.
设计合成了一系列苯醚键相连的C60-卟啉二元化合物及其金属锌配合物:H2Por-p-C60、H2Por-m-C60、H2Por-o-C60、ZnPor-p-C60、ZnPor-m-C60和ZnPor-o-C60,通过质谱、元素分析和核磁共振氢谱对它们的结构进行了表征。基态的电子吸收光谱和电化学研究表明在这些二元体系中C60和卟啉之间存在明显的相互作用。荧光光谱研究表明卟啉单元的荧光几乎被C60单元完全淬灭,并且它们之间的连接位置对荧光淬灭的效率具有显著影响。  相似文献   

14.
Bolger J  Miller M 《Tetrahedron letters》2011,52(17):2268-2271
Regioselective ring opening of N-hydroxycarbamate-derived nitroso cycloadducts by a copper-catalyzed allylic alkylation reaction was achieved and applied to the synthesis of a set of substituted diaryl ether containing compounds. Use of protected 3-hydroxybenzyl bromide allowed access to a late stage phenol intermediate after protection of the N-hydroxy moiety that was generated from the ring opening reaction. The diaryl ethers were then formed by copper-mediated coupling with arylboronic acids. After selective deprotection, alumina-promoted transcarbamoylation provided the target compounds. Previous results indicate that the compounds may possess significant inhibitory potency against the proinflammatory enzyme 5-lipoxygenase.  相似文献   

15.
Abstract

Three novel dicarboxylic acids, bis-4,4′-[N-4(4′-hydroxycarbonyl phenyleneoxy) phthalimido] diphenyl sulfone, bis-4,4′-[N-4(4′-hydroxycarbonyl phenyleneoxy) phthalimido] diphenyl methane, and bis-4,4′-[N-4(4′-hydroxycarbonyl phenyleneoxy) phthalimido] diphenyl ether, were synthesized, and several polyesterimides were prepared from diacid chlorides and bisphenols by solution polycondensation. The polymers were obtained in 65–88% yield and had inherent viscosities in the 0.18 to 0.64 dL/g range. The polymers were characterized by IR, elemental analysis, x-ray, TGA, DSC, and solubility tests. All the polymers were readily soluble in polar aprotic solvents and had a 10% weight loss temperature above 375°C in nitrogen.  相似文献   

16.
Five new proton-ionizable macrocyclic ligands containing a pyrimidone-subcyclic unit, 6–10 , were prepared from the previously prepared pyrimidinocrown ethers 1–5 (see Figure 1 and Scheme 1). One of the new proton-ionizable crown ethers is chiral. The proton-ionizable pyrimidonocrown ethers were prepared in high yields by treating the appropriate methoxy-substituted pyrimidinocrown with 5 M sodium hydroxide in a 50% alcohol-water mixture. Complexation properties of four of the pyrimidine-derived macrocycles were studied by various nmr techniques. Pyrimidono-18-crown-6 (9) forms a strong complex with benzylammonium perchlorate and also forms a complex with benzylamine. (S, S)-Dimethyl-substituted pyrimidino- and pyrimidono-18-crown-6 ligands 4 and 9 form stronger complexes with the (R)-form of α-(1-naphthyl)ethylammonium perchlorate than with the (S)-form. (S, S)-Dimethyl-substituted pyrimidono-18-crown-6 ( 9 ) also forms a stronger complex with (R)-α-(1-naphthyl)ethylamine than with the (S)-form. The crystal structure for compound 7 is reported.  相似文献   

17.
Two new tetra‐ or di‐α‐substituted zinc(II) phthalocyanines 5 and 6 have been prepared through a “side‐strapped” method. In the molecules, the adjacent benzene rings of the phthalocyanine core are linked at α‐position through a triethylene glycol bridge to form a hybrid aza‐/oxa‐crown ether. The tetra‐α‐substituted phthalocyanine 5 shows an eclipsed self‐assembly property in CH2Cl2 and the effect on the di‐α‐substituted analogue 6 is significantly weakened. Furthermore, the crown ethers of these compounds can selectively complex with Fe3+ or Cu2+ ion in DMF, leading to formation of J‐aggregated nano‐assemblies, which can be disaggregated in the presence of some organic or inorganic ligands, such as triethylamine, tetramethylethylenediamine, CH3COO?, or OH?. In addition, both compounds are efficient singlet oxygen generators with the singlet oxygen quantum yields (ΦΔ) of 0.54‐0.74 in DMF relative to unsubstituted zinc(II) phthalocyanine (ΦΔ=0.56). They exhibit photodynamic activities toward HepG2 human hepatocarcinoma cells, but the compound 6 , which has more than 40‐fold lower IC50 value (0.08 μM ) compared to the analogue 5 (IC50=3.31 μM ), shows remarkablely higher in vitro photocytotoxicity due to its significantly higher cellular uptake and singlet oxygen generation efficiency. The results suggest that these compounds can serve as promising multifunctional materials both in (opto)electronic field and photodynamic therapy.  相似文献   

18.
The mass spectra of some α-substituted phenyl-α,α′-dimethoxyl ketones (compounds 1) and their 2,4-dinitrophenylhydrazones (compounds 2) and semicarbazones (compounds 3) have been studied. The characteristic fragments at m/z (M ? 73) from compounds 1, m/z (M ? 253) from compounds 2 and m/z (M ? 130) from compounds 3 are abundant and proposed to be [ArCROCH3]+. Fragmentations yielding [M+ ? 49] from compounds 2 are abnormal and probably involve the methoxyl and nitro groups. The intense peak at m/z 130 due to [CH3OCH2CNNHCONH2]+ from compounds 3 corresponds to α-cleavage of the molecular ion. Some other fragments from these new compounds are interpreted in this paper.  相似文献   

19.
Due to their large possibility of the structure modification, alkylammonium gemini surfactants are a rapidly growing class of compounds. They exhibit significant surface, aggregation and antimicrobial properties. Due to the fact that, in order to achieve the desired utility effect, the minimal concentration of compounds are used, they are in line with the principle of greenolution (green evolution) in chemistry. In this study, we present innovative synthesis of the homologous series of gemini surfactants modified at the spacer by the ether group, i.e., 3-oxa-1,5-pentane-bis(N-alkyl-N,N-dimethylammonium bromides). The critical micelle concentrations were determined. The minimal inhibitory concentrations of the synthesized compounds were determined against bacteria Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538; yeast Candida albicans ATCC 10231; and molds Aspergillus niger ATCC 16401 and Penicillium chrysogenum ATCC 60739. We also investigated the relationship between antimicrobial activity and alkyl chain length or the nature of the spacer. The obtained results indicate that the synthesized compounds are effective microbicides with a broad spectrum of biocidal activity.  相似文献   

20.
Perfluorocyclohexano-15-crown-5 ether, trans- (1) and cis-(2) isomers have been prepared by direct fluorination using the LaMar fluorination technique1. They have several potential applications and are of special interest in a variety of fields2.  相似文献   

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