2,5-二取代-1,3,4-噻二唑衍生物的一锅法合成、结构表征及生物活性研究

采用超声波辐射与相转移催化联用技术, 一锅法合成出了8个新的2-(1-萘乙酰氨基)-5-芳氨甲基-1,3,4-噻二唑化合物, 这种合成方法具有反应条件温和、反应时间较短、产率较高等特点. 新化合物的结构利用IR, ¹H NMR, ¹³C NMR, 1D NOE, MS和元素分析进行了表征. 人环氧酶-2 (COX-2)活性抑制实验结果表明, 目标化合物5f对COX-2具有很强的抑制活性, 抑制率高达95.59%; 化合物5g对COX-2也具有一定的抑制活性. 目标化合物无抗惊厥活性.     

1-芳甲基-3-芳基吡唑-5-羧酸乙酯衍生物的合成与生物活性评价

在碳酸钾存在下, 以丙酮或乙腈为溶剂, 3-芳基吡唑-5-羧酸乙酯与芳甲基氯发生亲核取代反应, 以较好收率得到1-芳甲基-3-芳基吡唑-5-羧酸乙酯衍生物. 取代基以及溶剂对反应收率有较大影响. ¹H NMR, ¹³C NMR, IR和MS表征了化合物的结构. 通过X射线衍射分析测定了化合物3c的晶体结构. 所得化合物3a～3d在5～20 μmol•L^－1浓度范围对血管内皮细胞(HUVEC)凋亡具有促进活性, 其效果具有浓度依赖性.     

新型3-取代-6-(4-氯苯基)-7-(1H-1,2,4-三唑-1-基)-1',2',4'-三唑[3,4-b]-1",3",4"-噻二嗪衍生物的合成及抗菌活性

通过3-取代-4-氨基-5-巯基-1,2,4-三唑(3a～3m)和2-溴-2-(1H–1,2,4-三唑-1-基)-4′-氯代苯乙酮(2)的缩合反应, 合成了13个新型3-取代-6-(4-氯苯基)-7-(1H-1,2,4-三唑-1-基)-1',2',4'-三唑[3,4-b]-1",3",4"-噻二嗪衍生物4a～4m. 化合物结构经元素分析, ¹H NMR, IR和MS进行了表征. 抗菌试验表明所合成的化合物对细菌表现出中等程度的抑制活性.     

N-多氟烷基取代和葡萄糖基取代的1,2,4-三唑-5-硫酮类席夫碱的合成及其杀虫活性

为改善三唑类化合物的生物活性, 以3-苯基-4-氨基-1,2,4-三唑-5-硫酮为原料, 将其与芳香醛在冰醋酸体系中反应, 得到3-苯基-4-芳基亚甲氨基-1,2,4-三唑-5-硫酮类席夫碱(4a～4i). 在此基础上, 化合物4a～4i分别与多氟烷基碘代烷和溴代乙酰基葡萄糖反应合成了一系列1,2,4-三唑-5-硫酮类席夫碱的多氟烷基取代物5a～5r和葡萄糖基取代物6a～6d, 并用¹H NMR, ¹⁹F NMR, IR和MS谱以及元素分析表征了它们的结构. 初步生物活性测试结果表明, 部分目标化合物具有明显的杀虫活性.     

4-(取代嘧啶-2-基)-1-芳磺酰基氨基脲化合物的合成与表征

以取代的苯磺酰肼与(取代嘧啶-2-基)-氨基甲酸苯酯在非亲核性碱存在下合成了12个4-(取代嘧啶-2-基)-1-芳磺酰基氨基脲化合物5和3个5与碱形成的有机盐5as, 5bs和5cs. 所有合成化合物均经过元素分析和¹H NMR的结构确证. ¹H NMR数据证明, 在5as～5cs中, 磺酰氨基脲起到提供质子的作用.     

4-吡唑基-2-芳氧基嘧啶类化合物的合成及除草活性

以2,4-二氯嘧啶为起始原料, 利用两个氯原子的活性差异, 经4-吡唑基-2-氯嘧啶合成了一系列4-吡唑基-2-芳氧基嘧啶类化合物, 通过¹H NMR和元素分析对所合成的化合物进行了结构表征. 初步生物活性测定结果表明, 所合成的化合物都表现出一定的除草活性. 当嘧啶环2位的氯原子被芳氧基取代后, 化合物的除草活性均有不同程度的提高, 例如5c和4a相比, 100 μg•mL^－1时化合物对油菜的抑制率由15.7%提高到85.4%, 对稗草的抑制率由原来的11.6%提高到84.0%.     

2-甲硫基-7(5)-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯的区域选择性合成与2D NMR 研究

利用3-甲硫基-4-乙氧羰基-5-氨基-1H-吡唑分别与甲基/芳基烯胺酮反应, 合成了8种新的化合物2-甲硫基-7-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯(3a～3g)和2-甲硫基-5-甲基-3-吡唑并[1,5-a]嘧啶甲酸乙酯(4a). 化合物的结构均经元素分析, IR, ¹H NMR, MS所证实, 异构体3a和4a的结构进一步由¹³C NMR, HMQC和HMBC确认. 同时, 探讨了区域选择性合成吡唑并[1,5-a]嘧啶类化合物可能的反应机理, 并对部分化合物杀菌活性进行了测试.     

二吡唑基甲酮类化合物的合成和表征

以5-氨基-3-甲硫基-1H-吡唑-4-羧酸乙酯(1)为原料, 依次经肼解、与取代的乙烯酮二硫缩醛缩合和烷基化合成了一系列二吡唑基甲酮类化合物, 经¹H NMR, ¹³C NMR和元素分析确证了它们的结构, 部分化合物进一步经过了质谱表征.     

硫代氢化脲嘧啶的合成及其对Hill反应的抑制活性

为了寻找高活性的Hill反应抑制剂, 以β-氨基丙酸为原料, 经过四步反应, 合成了一系列未经文献报道的3-取代硫代氢化脲嘧啶. 所有新化合物的结构均经过¹H NMR, IR和元素分析证. 初步的生物活性测试表明, 所合成的化合物能有效地抑制Hill反应, 如化合物 5j 有很高的抑制活性(IC₅₀＝0.82 g•mL^－1).     

中国南海海绵Cinachyrella australiensis中(3E)-胆甾-4-烯-3,6-二酮-3-肟的结构鉴定

从南中国海海绵Cinachyrella australiensis的乙酸乙酯萃取部分分离出一个结构特别的甾体化合物, 应用UV, IR, MS, ¹H NMR, ¹³C NMR, DQCOSY, NOESY, TOCSY, HMQC和HMBC等光谱分析技术, 确定它为(3E)-胆甾-4-烯-3,6-二酮-3-肟(1). 化合物1为新天然甾体化合物, 通过生理活性实验表明其对乙肝病毒Hep G2细胞有较强的细胞毒活性. 本文对其波谱数据作了详细报道.     

Synthesis,Characterization, and Biological Activity of Substituted Thiazole-5-carboxaldehydes and Their Ylidenenitriles Derivatives

The Vilsmeier–Haack reaction of 2-amino -4-(4-substituted phenyl)-thiazoles 1, in the presence of micellar media, gives formylated derivatives 2, which upon hydrolysis afforded thiazole-5-carboxaldehydes 3. Microwave-assisted Knoevenagel condensation of 3 with active methylene compounds, in the presence of piperidine as catalyst, gives excellent yields of ylidenenitrile compounds 4. The structures of the newly synthesized compounds were established on the basis of elemental analysis, IR, ¹H NMR, and ¹³C NMR spectral analysis. All newly synthesized compounds were screened for antibacterial activity using two Gram-positive and one Gram-negative bacterial species and their antifungal activity was screened using two fungal species.     

Novel 5‐Methyl‐2‐[(un)substituted phenyl]‐4‐{4,5‐dihydro‐ 3‐[(un)substituted phenyl]‐5‐(1,2,3,4‐tetrahydroisoquinoline‐2‐yl)pyrazol‐1‐yl}‐oxazole Derivatives: Synthesis and Anticancer Activity

Eleven novel 5‐methyl‐2‐[(un)substituted phenyl]‐4‐{4,5‐dihydro‐3‐[(un)substituted phenyl]‐5‐(1,2,3,4‐tetrahydroisoquinoline‐2‐yl)pyrazol‐1‐yl}‐oxazole derivatives were synthesized and characterized by elemental analysis, ESI‐MS, ¹H NMR and ¹³C NMR. All of the compounds have been screened for their antiproliferative activities against PC‐3 cell (human prostate cancer) and A431 cell (human epidermoid carcinoma cancer) lines in vitro. The results revealed that compounds 4g , 4j and 4k exhibited the strong inhibitory activities against the PC‐3 cell lines (with IC₅₀ values of 2.8±0.11, 3.1±0.10 and 3.0±0.06 μg/mL, respectively).     

Chemical constituents from the roots of <Emphasis Type="Italic">Senecio scandens</Emphasis>

The chemical constituents of the roots of Senecio scandens Buch.-Ham. grown in the Funiu mountains in China have been investigated. Four compounds were isolated and identified as β−sitosterol (1), pentacosanoic acid (2), 19α-H lupeone (3), and sucrose (4). The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence. 19α-H Lupeone (3) was isolated as a single compound and its structure established unambiguously by the spectral method for the first time, and ¹H and ¹³C NMR data were assigned wholly by 1D and 2D NMR.     

A new lactam alkaloid from Portulaca oleracea L. and its cytotoxity

A new lactam alkaloid named oleraciamide D (1), indentified as (5R)-4-(3-methoxy-4-hydroxyphenyl)-5-(4-hydroxyphenyl)-5,6-dihydropyridin-2(1H)-one, together with five known compounds, indole-3-aldehyde (2), portulacatone (3), N-trans-feruloyloctopamine (4), N-trans-feruloyl-3′-O-methyldopamine (5) and N-trans-feruloyltyramine (6) were isolated from Potulaca oleracea L. Among them, indole-3-aldehyde (2) was isolated from the medicine for the first time. The structure of the new alkaloid was elucidated via UHPLC-ESI-Q-TOF/MS, 1D NMR and 2D NMR. The five known compounds were established by comparing the ¹H-NMR and ¹³C NMR with the reported literature. Oleraciamide D (1) showed cytotoxicity against SH-SY5Y cells when concentration at 50 uM by CCK-8 method.     

Synthesis and biological activity of ethyl 2-(5-methyl-3-arylisoxazole-4-carboxamido)-4-alkylthiazole-5-carboxylate

A series of novel ethyl 2-(5-methyl-3-arylisoxazole-4-carboxamido)-4-alkylthiazole-5-carboxylates I-1-6 were synthesized. The structures of all target compounds were characterized by ¹H NMR, ¹³C NMR, IR, MS and elemental analyses. Their fungicidal and herbicidal activities were evaluated. The results of preliminary bioassays show that the title compounds I-4 possess 20–50% inhibition against most of the tested plants at the dosage of 150 g ai/ha, while the title compounds I-1-5 possess 32–58% inhibition against FusaHum graminearum, Thanatephorus cucumeris, Botrytis cinereapers and Fusarium oxysporum in vitro at the concentration of 100 mg/L.     

The photo-physicochemical properties of an octa-substituted zinc phthalocyanine containing 1,2,4-triazole moieties

4,5-Bis(2-(4-(4-methoxybenzylamino)-5-oxo-3-p-tolyl-4,5-dihydro-1H-1,2,4-triazol-1-yl)ethoxy)-substituted zinc(II) phthalocyanine (4) was synthesized from a phthalonitrile derivative (3). The compounds were characterized by several spectral methods such as electronic absorption, FT-IR, ¹H NMR, ¹³C NMR, mass spectrometry, and elemental analyses. The photophysical and the photochemical properties of 4 were investigated in DMSO and DMF. The solvent effect on the photochemical and photophysical properties for 4 is also discussed.     

New dammarane and ursane-type triterpenoids from the flower of Ixora coccinea Linn.

Two new esters of dammarane triterpenoids ixorene isovalerate (1), ixorene 3′,8′-dimethyloctanoate (2) and a new ursane-type triterpenoids Ixoroid acid (3) were isolated from the methanolic extract of flowers of Ixora coccinea Linn., along with the three known constituents. The structures of compounds 1 and 3 were elucidated on the basis of extensive 1D,2D NMR studies and mass spectrometry as 17β-dammara-12,20-diene-3β-isovelarate and 3β-hydroxy-18β-urs-12ene-29β-oic acid, respectively, whereas 2 was identified as 17β-dammara-12,20-diene-3β-3′,8′-dimethyloctanoate through ¹H NMR and mass spectral data. Compounds 1, 2, 4 and 5 were evaluated for their in vitro cytotoxic activity, which exhibited weak activity against the 3T3, PC3 and HeLa cell lines with the IC₅₀ value >30 μM. Antioxidant results of 1 – 5 revealed that only compound 5 showed antioxidant activity in DPPH radical scavenging inhibition with the IC₅₀ 1.31 × 10^? 6 ± 0.005 μm mL^? 1. Both activities are the first records of these isolated compounds from the flowers of Ixora coccinea Linn.     

Syntheses,spectroscopic and crystallographic characterizations of 4-nitrobenzyloxy derivatives and benzofurans from <Emphasis Type="Italic">ortho</Emphasis>-substituted benzaldehydes and 4-nitrobenzyl bromide

A series of benzyloxybenzaldehyde derivatives (1–3) were prepared by the reactions of 4-nitrobenzyl bromide with 4-hydroxy-3-methoxybenzaldehyde (vanillin), 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 2-hydroxy-4-methoxybenzaldehyde. When the reaction time is quite long, benzofuran derivatives (4 and 5) were obtained by the reactions of ortho-hydroxyaldehydes with the 4-nitrobenzyl bromide. Condensation reactions among the three benzyloxybenzaldehyde derivatives (1–3) with 2-aminomethylfuran (furfurylamine) yielded the new imine compounds (6–8). The structures of these aldehydes (1–3), benzofuran derivatives (4 and 5) and imine compounds (6–8) were confirmed on the basis of elemental analyses, IR, ¹H NMR and ¹³C NMR and mass spectroscopy. The solid-state structures of compounds 4–6 were determined by single-crystal X-ray crystallography.     

A NOVEL SYNTHESIS OF ISOXAZOLES VIA 1,3-DIPOLAR CYCLOADDITION OF NITRILE OXIDES TO ACETYL ACETONE

ABSTRACT

Nitrile oxides (2) isolated from the oxidative dehydrogenation of aldoximes (1) by chloramines-T react with acetyl acetone (3) to afford 4-acetyl-3-aryl-5-methyl isoxazoles (5) in good yield. All new compounds were characterized by IR, ¹H NMR, ¹³C NMR, MS studies and elemental analysis.