Diastereoselective alkylation reactions of 1-methylcyclohexa-2,5-diene-1-carboxylic acid

The deprotonation and alkylation of 1-methylcyclohexa-2,5-diene-1-carboxylic acid has been investigated under a range of conditions. In all cases, the formation of compounds 14 was found to be completely stereoselective, although compound 14c was formed as an impurity when alkyl iodides were used as electrophiles, and doubly-alkylated compounds 17 were formed in some cases when alkyl bromides were used.     

Synthesis of 1-propylsulfanylhexane aminomethoxy derivatives

Synthesis was performed of new aminomethoxy derivatives of 1-propylsulfanyl hexane by Mannich condensation of 1-propanethiol, secondary amines, and formaldehyde. The structure of compounds synthesized was established by elemental analysis, mass spectrometry, IR and ¹H NMR spectroscopy. Some compounds obtained were tested as antimicrobial additives to lubricating oils, and also as antiseptics against bacteria and fungi. It was established that these compounds are more efficient antimicrobial substances than the preparations currently used.     

Syntheses of the metabolites of 1-(2-ethoxyethyl)-2-(hexahydro-4-methyl-1H-1,4-diazepin-1-yl)-1H benzimidazole difumarate (KG-2413) and related compounds

The metabolites of 1-(2-ethoxyethyl)-2-(hexahydro-4-methyl-1H-1,4-diazepin-1-yl)-1H-b enzimidazole difumarate (KG-2413), which has a potent H1-antihistaminic activity, were predicted on the basis of metabolic studies of related compounds and were synthesized to aid in identification of the actual metabolites and for examination of their antihistaminic activity. Among the twelve compounds prepared, nine compounds were actually found as the metabolites of KG-2413 in rat urine. The antihistaminic activities of these metabolites were found to be lower than that of KG-2413.     

益母草碱类似物设计、合成及其Na+/H+交换器-1抑制活性

以中药益母草中有效成分益母草碱为先导化合物,按生物电子等排原理,设计合成了18个益母草碱类似物.通过MS,1H NMR,13C NMR对化合物结构进行表征.初步的药效研究结果表明部分化合物具有Na+/H+交换器-1 (NHE-1)抑制活性,其中化合物1a和1e的活性显著强于阳性对照药Cariporide.     

Synthesis of methyleneoxyamino derivatives of 1-butylthioheptane

The possibility of synthesizing new methyleneoxyamino derivatives of 1-butylthioheptane was investigated. The structure of the synthesized compounds was proved by elemental analysis and IR and ¹H NMR spectroscopy. Some representatives of the synthesized compounds were tested as antimicrobial lubricant additives, and also as antiseptic materials against bacteria and funguses.     

Synthesis and antineoplastic properties of (1H-1,2,3-triazol-1-yl)furazans

A method of 3-amino-4-[5-aryl(heteroaryl)-1H-1,2,3-triazol-1-yl)]furazan synthesis was optimized. Condensation of these compounds with 2,5-dimethoxytetrahydrofuran resulted in a series of previously unknown 4-[5-aryl(heteroaryl)-1H-1,2,3-triazol-1-yl)]-3-(pyrrol-1-yl)furazans. All target compounds were evaluated for both antimitotic microtubule destabilizing effect in a phenotypic sea urchin embryo assay and cytotoxicity in a panel of 60 human cancer cell lines. Pyrrolyl derivatives of triazolylfurazans were determined as antiproliferative compounds. The most potent microtubule targeting compounds 7a and 7e are of interest for further trials as antineoplastic agents.     

Preparation and mesomorphic properties of 1-methyl-1H-benzimidazole-based compounds

A series of 1-methyl-1H-benzimidazole-based compounds, 2-(4?-alkoxy-1,1?-biphenyl-4-yl)-1-methyl- 1H-1,3-benzimidazole derivatives (nPPMx-M) with terminal hydrogen, methyl and nitro moieties (coded as nPPMH-M, nPPMM-M and nPPMN-M, respectively), were prepared and their structures were characterised. The compounds display enantiotropic smectic mesophases for hydrogen and methyl terminated compounds (nPPMH-M and nPPMM-M), and enantiotropic nematic mesophases for nitro terminated compounds (nPPMN-M) with short alkoxy chain below than 10 carbon atoms, where the mesophase ranges are 24–72°C and 74–104°C on heating and cooling processes for nPPMH-M, 90–119°C and 110–135°C for nPPMM-M, and 102–129°C and 113–207°C for nPPMN-M, respectively. It is noted that the compounds nPPMx-M exhibit much lower melting points and much wider mesophase range both in heating and cooling than non-1-methyl substituted analogs, which are ascribed to the disruption of hydrogen bonding among the molecules caused by methyl substitution at 1-position of benzimidazole. Meanwhile, among the compounds nPPMx-M, much wider mesophase ranges are obtained for nPPMM-M and nPPMN-M, indicating a much high mesophase stability for the compounds bearing terminal moiety (CH₃ and NO₂).     

1-磺酰基-3,5-二氨基-1H-吡唑-4-腈的合成及其生物活性

除草剂;1-磺酰基-3;5-二氨基-1H-吡唑-4-腈的合成及其生物活性     

3,3-二甲基-1-(1H-1,2,4-三唑-1-基)-2-丁酮及1-(1H-1,2,4-三唑-1-基)取代苯乙酮与二溴化物的关环反应及产物的生物活性

通过二溴化物与唑酮1[R=(CH₃)₃C]或α-三唑基苯乙酮1(R=Ar)的亲核取代反应,合成了新型的环状三唑类化合物3和4,经元素分析,¹HNMR,IR,EI-MS和X射线衍射等方法确证其结构,讨论了反应过程.生物活性测试发现大部分化合物具有很好的杀菌活性,尤其对小麦锈病具有较强的抑制作用.     

Convenient Synthesis of 1-Thiohydroxypyrene by Newman-Kwart Rearrangement

1-Thiohydroxypyrene(1) and its two intermediates, 1-pyrenyl-O-thiocarbamate(2) and 1-pyrenyl-S-thio- carbamate(3), were synthesized using 1-hydroxypyrene as the starting material. The key synthetic step is Newman-Kwart rearrangement. The results indicate that the Newman-Kwart rearrangement is more effective in suitable solvent than conventional method based on pure organic compound. The structures of compounds 1―3 were characterized by FTIR, NMR, GC-MS and elementary analysis. The crystal structures of two new compounds(2 and 3) were determined by single crystal X-ray diffraction analysis. The whole synthetic process is simple, mild and with high yield.     

3-取代-3-苯基-1-茚酮类化合物的合成

以3-苯基-1-茚酮（1）为原料,THF为溶剂,二异丙基氨基锂（LDA）为碱,与碘代烷（RI）经亲核取代反应合成了4个3-取代-3-苯基-1-茚酮类化合物（3a~3d),其中3b~3d为新化合物,其结构经¹H NMR, ¹³C NMR 和EI-GC-MS表征。在最佳反应条件［1 1.0 eq., LDA/RI=2.1/1.5（当量比）,于0 ℃~rt反应5 h］下,3a~3d收率为70％～80％。     

以1-甲基-1-甲氧基乙基为保护基的一锅法合成5-芳香二酮-1H-四氮唑

报道了5-芳香二酮-1H-四氮唑(2)的一锅合成法,并且首次报道了1-甲基-1-甲氧基乙基作为四氮唑氮原子的保护基团,保护与脱保护反应条件温和,操作简便,收率高,为该类化合物的合成提供了一条捷径.采用该方法共合成6个未见文献报道的5-芳香二酮-1H-四氮唑类新化合物,以用于药理活性筛选.     

Synthesis and properties of aminomethoxy derivatives of 1-(butylsulfanyl)pentane

New aminomethoxy derivatives of 1-(butylsulfanyl)pentane have been synthesized. The structure of the synthesized compounds was studied by elemental analysis, IR and ¹Н NMR spectroscopy, and mass spectrometry. Some specimens of the synthesized compounds were tested as antimicrobial additives to lubricant oil, and as aseptic compounds against bacteria and fungi.     

Design,Synthesis and Structure-activity of N-Glycosyl-1-pyridyl-1H-pyrazole-5-carboxamide as Inhibitors of Calcium Channels

Carbohydrates, with broad-spectrum structures and biological functions, are key organic compounds in nature, along with nucleic acids and proteins. As part of our ongoing efforts to develop a new class of pesticides with novel mechanism of action, a series of novel N-glycosyl-1-pyridyl-1H-pyrazole-5-carboxamide was designed and synthesized via the reactions of glycosyl methanamides and pyridyl-pyrazole acid. The compounds were characterized by ¹H NMR and ¹³C NMR. The bioassay results indicate that some of these compounds exhibit moderate insecticidal activities and assessed as potential inhibitors of calcium channels. The modulation of voltage-gated calcium channels by compounds 4a and 5a in the central neurons isolated from the third instar larvae of Spodoptera exigua was studied by whole-cell patch-clamp technique. In addition, compound 5a inhibits the recorded calcium currents reversible on washout. Experimental results also indicate that compound 5a did not release stored calcium from the Endoplasmic Reticulum. The present work demonstrates that N-glycosyl-1-pyridyl-1H-pyrazole-5-carboxamides cannot be used as possible inhibitors of calcium channels for developing novel pesticides.     

3-芳氧基-6-(3,5-二甲基-1H-吡唑-1-基)哒嗪的合成及生物活性

为了寻找高活性的先导化合物, 以3,6-二氯哒嗪为原料, 经过三步反应, 合成了一系列未经文献报道的3-芳氧 基-6-(3,5-二甲基-1H-吡唑-1-基)哒嗪. 所有新化合物的结构均经过¹H NMR, IR, LC-MS和元素分析确认. 初步的生物活性测试表明, 所合成的化合物都有一定的除草活性.     

The preparation and the nucleophilic reaction of 3,3-di(1-azolyl)-2-alken-1-ones,precursor of acetylketene derivatives

2-Alken-1-ones, 3,3-di-(1-azolyl)-2-alken-1-ones and related compounds were prepared by two methods. These compounds were found to be the useful precursors for acylketene derivatives such as ketene dithioacetals and diaminals by treatment with various nucleophiles.     

The antioxidant profile of 2,3-dihydrobenzo[b]furan-5-ol and its 1-thio, 1-seleno, and 1-telluro analogues

A novel synthesis of 2,3-dihydrobenzo[b]thiophene-5-ol based on intramolecular homolytic substitution on sulfur was reported. The "antioxidant profile" of the series of 2,3-dihydrobenzo[b]furan-5-ol (2a) its 1-thio (2b), 1-seleno (2c) and 1-telluro (2d) analogues was determined by studies of redox properties, the capacity to inhibit stimulated lipid peroxidation, the reactivity toward tert-butoxyl radicals, the ability to catalyze decomposition of hydrogen peroxide in the presence of glutathione, and the inhibiting effect on stimulated peroxidation in liver microsomes. The one-electron reduction potentials of the aroxyl radicals corresponding to compounds 2a-2d, E degrees (ArO(*)/ArO(-)) were 0.49, 0.49, 0.49, and 0.52 V vs NHE, respectively, as determined by pulse radiolysis. With increasing chalcogen substitution the compounds become slightly more acidic (pK(a) = 10.6, 10.0, 9.9, and 9.5, respectively, for compounds 2a-2d). By using Hess' law, the homolytic O-H bond dissociation enthalpies of compounds 2a-2d (340, 337, 336, and 337 kJ mol(-)(1), respectively) were calculated. The reduction potentials for the proton coupled oxidation of compounds 2a-2d (ArOH --> ArO(*) + H(+)) as determined by cyclic voltammetry in acetonitrile were 1.35 (irreversible), 1.35 (quasireversible) 1.13 (reversible), and 0.74 (reversible) V vs NHE, respectively. As judged by the inhibited rates of peroxidation, R(inh), in a water/chlorobenzene two-phase lipid peroxidation system containing N-acetylcysteine as a thiol-reducing agent in the aqueous phase, the antioxidant capacity increases (2d > 2c = 2b > 2a) as one traverses the group of chalcogens. Whereas the times of inhibition, T(inh), were slightly reduced for the oxygen (2a) and sulfur (2b) derivatives in the absence of the thiol-reducing agent, they were drastically reduced for the selenium (2c) and tellurium (2d) derivatives. This seems to indicate that the organochalcogen compounds are continuously regenerated at the lipid aqueous interphase and that regeneration is much more efficient for the selenium and tellurium compounds. The absolute rate constants for the oxidation of compounds 2a-2b by the tert-butoxyl radical in acetonitrile/di-tert-butyl peroxide (10/1) were the same-2 x 10(8) M(-)(1) s(-)(1). Whereas the oxygen, sulfur, and selenium derivatives 2a-2c were essentially void of any glutathione peroxidase-like activity, the organotellurium compound 2d accelerated the initial reduction of hydrogen peroxide, tert-butyl hydroperoxide, and cumene hydroperoxide in the presence of glutathione 100, 333, and 213 times, respectively, as compared to the spontaneous reaction. Compounds 2a-2d were assessed for their capacity to inhibit lipid peroxidation in liver microsomes stimulated by Fe(II)/ADP/ascorbate. Whereas the oxygen, sulfur, and selenium compounds showed weak inhibiting activity (IC(50) values of approximately 250, 25, and 13 microM, respectively), the organotellurium compound 2d was a potent inhibitor with an IC(50) value of 0.13 microM.     

Virtual screening for anti-HIV-1 RT and anti-HIV-1 PR inhibitors from the Thai medicinal plants database: a combined docking with neural networks approach

The virtual screening approach for docking small molecules into a known protein structure is a powerful tool for drug design. In this work, a combined docking and neural network approach, using a self-organizing map, has been developed and applied to screen anti-HIV-1 inhibitors for two targets, HIV-1 RT and HIV-1 PR, from active compounds available in the Thai Medicinal Plants Database. Based on nevirapine and calanolide A as reference structures in the HIV-1 RT binding site and XK-263 in the HIV-1 PR binding site, 2,684 compounds in the database were docked into the target enzymes. Self-organizing maps were then generated with respect to three types of pharmacophoric groups. The map of the reference structures were then superimposed on the feature maps of all screened compounds. Only the structures having similar features to the reference compounds were accepted. By using the SOMs, the number of candidates for HIV-1 RT was reduced to six and nine compounds consistent with nevirapine and calanolide A, respectively, as references. For the HIV-1 PR target, there are 135 screened compounds showed good agreement with the XK-263 feature map. These screened compounds will be further tested for their HIV-1 inhibitory affinities. The obtained results indicate that this combined method is clearly helpful to perform the successive screening and to reduce the analyzing step from AutoDock and scoring procedure.     

Studies on 1, 2, 4-Benzothiadiazine 1, 1-Dioxide IX.1 Synthesis and Pharmacological Evaluation of 1, 2, 4-Benzothiadiazine 1, 1-Dioxide Biphenyl Tetrazoles as Angiotensin II Antagonists

In the course of our investigations on the development of cardiovascular agents, 3-butyl-2-[2′-(2H-tetrazol-5-yl)bipheny]-4-yl]methyl-2H-1, 2, 4-benzothiadiazine 1, 1-dioxide ( 2 ) was considered as a potential angiotensin II antagonist on the basis of bioisosteric replacement of the quinazoline ring of compound 1 with a 1, 2, 4-benzothiadiazine 1, 1-dioxide ring system. Alkylation of 6 with 4 afforded 7 and 8 in 24% and 28% yields, respectively. An attempt to remove the trityl group of compounds 7 and 8 under acidic condition gave the ring opened products 9 and 11 in 28% and 36% yields, respectively. However, compounds 2 and 10 were obtained in 46% and 85% yields when compounds 7 and 8 were refluxed in methanol. Preliminary assays of compounds 9 and 11 against angiotensin II receptors revealed weak activity with IC₅₀ values of 3.6 μM and 5.4 μM, respectively. Compound 10 (IC₅₀ = 87 nM) exhibited stronger binding affinity than compound 2 (IC₅₀ = 750 nM).     

1-取代-顺式-1,2-环己二醇单磺酸酯类酸增殖剂的合成和性质研究

用过氧化氢氧化烯烃得到顺式邻环己二醇,继而和对甲苯磺酰氯反应得到两种1-取代-顺式-1,2-环己二醇单磺酸酯.以溴酚兰作指示剂,用作者自己的方法定量测定了它们在聚乙二醇膜层中的酸解性能.结果表明,在光产酸剂所产酸作用下,在加热条件下这些化合物发生分解并产酸.这两个磺酸酯的储存稳定性不是很好,在极性溶剂作用下易分解,限制了它们在化学增幅型成像材料中的应用.