无溶剂无催化剂条件下芳香醛与3-甲基异噁唑-5-酮的缩合反应

在无溶剂无催化剂条件下, 芳香醛与3-甲基异噁唑-5-酮经室温研磨和固相加热发生缩合反应得到了系列3-甲 基-4-芳亚烃基异噁唑-5-酮. 产物的结构经¹H NMR, IR, MS和元素分析确证.     

温和条件下对甲基苯磺酸铝高效催化一锅法合成β-氨基酮衍生物

室温条件下,对甲基苯磺酸铝可有效催化芳香酮、芳香醛和芳香胺的Mannich反应,三组分"一锅法"合成了一系列β-氨基酮衍生物.考察了溶剂及反应条件对产率的影响.反应结束后,催化剂经简单相分离可回收并多次重复使用,催化活性无明显下降.产物结构经IR,~1H NMR,元素分析进行表征.     

铁氰化钾-钙黄绿素化学发光体系测定酮替芬的研究

发现钙黄绿素可以吸收铁氰化钾氧化酮替芬反应的化学能而产生化学发光, 以钙黄绿素为化学发光试剂, 构建了铁氰化钾-酮替芬-钙黄绿素化学发光体系, 利用此体系建立了测定酮替芬的化学发光分析新方法, 方法的线性范围为2.0×10^－8～6.0×10^－6 g•mL^－1, 检出限为8×10^－9 g•mL^－1, 对浓度为5.0×10^－7 g•mL^－1酮替芬溶液进行11次平行测定的相对标准偏差(RSD)为2.1%. 此法已用于药品中酮替芬含量的测定, 结果与药典测定结果一致. 对化学发光反应的机理也进行了初步的探讨.     

(±)-6,7-丙酮缩二醇-3-酮-庚酸乙酯合成研究

用对甲苯磺酸-2,3-丙酮缩甘油酯(2)与乙酰乙酸乙酯盐、碳酸二乙酯反应, 制备β-酮酯类衍生物1. 以(±)-1,2-丙酮缩甘油为起始物, 经对甲苯磺酰化、亲核取代、脱羧等反应, 方便、高产率地合成了6,7-丙酮缩二醇-3-酮-庚酸乙酯(1). 试图通过对甲苯磺酸-2,3-丙酮缩甘油酯(2)和乙酰乙酸乙酯双阴离子反应制备6,7-丙酮缩二醇-3-酮-庚酸乙酯(1)未获成功. 所合成的化合物经元素分析, IR, ¹H NMR, ¹³C NMR和MS光谱表征.     

无溶剂、无催化剂条件下合成1,4,5,6,7,8-六氢喹啉-5-酮衍生物

无溶剂、无催化剂条件, 在NH₄OAc存在下以查尔酮和1,3-二酮为原料, 高产率地合成1,4,5,6,7,8-六氢喹啉-5-酮衍生物. 该方法具有反应条件温和、操作简单和环境友好等优点. 并通过IR, ¹H NMR, 元素分析和X衍射确证产物的结构.     

5-(色酮-3-亚甲基)-3-芳基硫乙内酰脲的合成

以α-氨基乙酸和芳基异硫氰酸酯为起始原料制备3-芳基-2-硫乙内酰脲, 然后在酸性条件下与3-甲酰基色酮发生类Knoevenagel缩合反应, 合成得到了16种新的5-(色酮-3-亚甲基)-3-芳基硫乙内酰脲类化合物. 所有化合物的结构均经IR, ¹H NMR, LC-MS和元素分析确证, 并做了初步的生理活性测试     

二(三甲硅亚甲基)锡二芳香羧酸酯的合成和结构表征

用二(三甲硅亚甲基)二氯化锡与芳香酸按1∶2的摩尔比进行反应, 合成了11个新的含硅有机锡化合物二(三甲硅亚甲基)锡二芳香羧酸酯. 通过IR, ¹H NMR, ¹³C NMR, MS以及元素分析对这些化合物的结构进行了表征. 部分化合物生物活性的初步测定结果表明, 该类化合物对肺癌细胞SPC-A-1具有较好的体外抗癌活性.     

2-(3-芳氧甲基-4-苯基-1,2,4-三唑-5-硫基)乙酸的微波合成及生物活性研究

在微波辐射条件下, 芳氧乙酰肼经两步反应制得4-苯基-3-芳氧甲基-1,2,4-三唑-5-硫酮衍生物, 再与氯乙酸反应得到6种尚未见文献报道的2-(3-芳氧甲基-4-苯基-1,2,4-三唑-5-硫基)乙酸衍生物. 目标化合物的结构经IR, ¹H NMR和元素分析进行了确证. 生物活性试验结果表明, 该类化合物对双子叶植物油菜具有良好的生物调节活性.     

水中2,4,6-三芳基-3-芳酰基-4-羟基环己基-1,1-二甲腈的洁净合成

研究了十六烷基三乙基溴化铵(HTEAB)催化、水介质中, 查尔酮和丙二腈加热回流合成系列2,4,6-三芳基-3-芳酰基-4-羟基环己基-1,1-二甲腈化合物. 产物经¹H NMR, IR和元素分析进行了结构表征. 此方法具有反应条件温和、操作简便、产率较高、环境友好的优点.     

环己酮与查尔酮的无溶剂Michael加成反应

以环己酮和查尔酮为原料, 在 NaOH 存在下无溶剂室温研磨反应, 非常方便地得到Michael加成产物. 该方法具有反应条件温和、操作简单和产率较高等优点, 并通过IR, ¹H NMR和元素分析确证产物的结构.     

4-芳亚甲基-4,5-二氢-1,3-二苯基吡唑-5-酮的一锅法合成

报道了以乙酸为催化剂,由苯甲酰乙酸乙酯、苯肼和芳香醛经三组分一锅法缩合制备4-芳亚甲基-4,5-二氢-1,3-二苯基吡唑-5-酮衍生物的新方法.该方法缩短了反应时间,得到了中等产率.产物结构经MS,1HNMR,IR和元素分析确证.     

Homolytic substitutions in indolinone nitroxide radicals—II: Reaction with organic peracids

The reactions of indolinone nitroxides 7 and of the corresponding amine precursors 15 with organic peracids were studied, and were found to give substitution products at the aromatic nucleus, i.e. 5-aroyloxy- and 7-aroyloxynitroxides 8 together with N-oxides 10 and with 7-hydroxynitroxides 9. Structures were assigned on the basis of ESR and ¹H NMR spectra. A reaction scheme was proposed involving a homolytic substitution which accounts for the products obtained and is supported by an experimental proof.     

Organosulphur compounds—XVIII: A new and general synthesis of ketene s,s- and o,s-thioacetals based on the horner-wittig reaction

A new and general synthesis of ketene S,S-thioacetals (1) and ketene O.S-thioacetals (6) which involves the Horner-Wittig reaction of carbonyl compounds with the metallated S,S- and O,S-thioacetals of formyl-phosphonates (4 and 5) is described. The Horner-Wittig reaction of 4 with aromatic aldehydes can be carried out under two-phase conditions. The generation of the carbanions from 4 and 5 as well as the course of their reaction with carbonyl compounds were studied by the low temperature ³¹P NMR spectroscopy. It was found that S,S-thioacetals of formylphospbonates (4) are very easily metallated in contrast to O,S-thioacetals of formyl-phosphonates (5) which form the lithium derivatives only on treatment with t-butyllitnium. No evidence was obtained from ³¹P NMR spectra supporting the formation of the lithium derivatives of 0,0-acetals of formyl-phosphonates (12).     

Ultrasound mediated green synthesis of pyrano[2,3-c]pyrazoles by using Mn doped ZrO2

Mn doped zirconia is utilized as an environmental-friendly and efficient catalyst for an ultrasound mediated four-component coupling reaction, containing dimethylacetylenedicarboxylate/ethyl acetoacetate, hydrazine hydrate, malononitrile, and aromatic aldehyde. These reactions were performed under green solvent conditions, to yield pyrano[2,3-c]pyrazole-3-carboxylate/pyrano[2,3-c]pyrazole-5-carbonitrile derivatives (5a–g and 7a–g) with good to excellent yields (88–98%). The structures of the compounds were identified and confirmed by ¹H NMR, ¹⁵N NMR, ¹³C NMR, FT-IR and HR-MS spectral data. The prepared catalyst Mn/ZrO₂ was synthesized and fully characterized by various techniques including P-XRD, BET, SEM and TEM analysis. The main benefits of this process are short reaction times, easy work-up, reusability of the catalyst and no chromatographic purifications.     

Microwave-assisted synthesis of pyrazolo[3,4-d]pyrimidines from 2-amino-4,6-dichloropyrimidine-5-carbaldehyde under solvent-free conditions

The microwave-induced synthesis of pyrazolo[3,4-d]pyrimidines 4 in the reaction of N⁴-substituted-2,4-diamino-6-chloro-5-carbaldehydes 3 with hydrazine is described here. Precursors 3 have been prepared by the mono-amination of 2-amino-4,6-dichloropyrimidine-5-carbaldehyde 2 with aliphatic and aromatic amines. The reaction times with primary amines were relatively shorter than for secondary amines.     

The total synthesis of (±)-naphthyridinomycin. II. Construction of the pentacyclic carbon skeleton.

A synthesis of an advanced pentacyclic intermediate to the quinone antibiotic naphthyridinomycin (1) is described. The stereoselective synthesis of 2b from tricyclic lactam 3¹ features a regio- and stereoselective, intermolecular amidoalkylation reaction and a Friedel-Crafts ring closure to annelate the aromatic nucleus.     

Triazolyl C-nucleosides via the intermediacy of β-1′-ethynyl-2′-deoxyribose derived from a Nicholas reaction: Synthesis,photophysical properties and interaction with BSA

We report the design and synthesis of triazolyl donor/acceptor unnatural C-nucleosides via alkyne (sugar)—azide (aromatic) 1, 3-dipolar cyclo-addition reaction as a key step and studies on their photophysical properties. We have chosen β-1′-ethynyl-2′-deoxyribose as a precursor to synthesize triazolyl-C-nucleosides. Overcoming the difficulties, we obtain β-1′-ethynyl-2′-deoxyribose as a major product following a Co₂(CO)₈ catalyzed intramolecular Nicholas reaction. The 1,3-diaxial interaction is the driving force for the α to β-anomeric conversion while performing cobalt complexation followed by oxidation to afford β-1′- ethynyl-2′-deoxyribose as the major product. A Cu(I)-catalyzed click reaction between different aromatic donor/acceptor azides and β-1′- ethynyl-2′-deoxyribose generates the desired unnatural triazolyl donor-acceptor aromatic C-nucleosides (^cTB_Do/Ac) within 30 min. Single crystal X-ray structure shows the puckered conformation of sugar as C3′-exo. Studies on the photophysical properties suggests good fluorophoric as well as solvatochromic characteristics of these nucleosides. Two of the synthesised nucleosides, ^cTAnthB_Do and ^cTPyB_Do, are found to interact with BSA as the only tested protein with quenching of fluorescence signal. The designed bases, thus, might find applications in stabilizing a DNA and in the biophysical study thereof, if a pair of such donor acceptor C-nucleosides could be incorporated into a DNA sequence.     

Iodine catalyzed one-pot multi-component reaction to CF3-containing spiro[indene-2,3′-piperidine] derivatives

In the presence of a catalytic amount of molecular iodine (0.1 equiv.), the one-pot multi-component reaction of ethyl trifluoroacetoacetate 1, indan-1,3-dione 2, ammonium acetate 3 and aromatic aldehyde 4 mainly gave the ethyl-6′-hydroxy-1,3-dioxo-2′,4′-diaryl-6′-(trifluoromethyl)-1,3-dihydrospiro[indene-2,3′-piperidine]-5′-carboxylate derivatives 5, along with the minor product 2-trifluoromethyl-2,3,4,5-tetrahydro-1H-indeno[1,2-b]pyridine derivatives 6. A plausible reaction mechanism for the formation of 5, 6 was presented. The structures of compounds 5, 6 were fully confirmed by ¹H NMR, ¹⁹F NMR, MS, IR spectroscopies and elemental analysis or high resolution mass spectra (HRMS). Meanwhile, the representative 5a and 6h were further confirmed by XRD analysis.     

Photochemical behaviour of 5-bromo-2-furyl ketones : Synthesis of 5-aryl-2-furyl ketones

The photochemical behaviour of the compound 8 was studied. The irradiation of a 10^-3M solution of 8 in aromatic solvents gave high yields of 9 The irradiation of 8 in ethereal or amine solution quantitatively gave 10 The comparison of reaction rates and quantum yields in different solvents gave results in agreement with the hypothesis of an exciplex formation.     

Synthesis and biological evaluation of some novel N-arylpyrazole derivatives as cytotoxic agents

A series of novel N-arylpyrazole derivatives, 5a–5i, were achieved from substituted phenylacetic acid via Vilsmeier–Haack reaction, hydrolysis, condensation, and aromatic substitution reaction. Their chemical structures were confirmed by ¹H NMR, ¹³C NMR, FTIR, HRMS, and elemental analysis. The newly synthesized compounds were tested for their in vitro cytotoxic activity against Bel-7402, KB, HL-60, and BGC-823 cell lines and found to possess moderate activity.