3-芳胺甲烯基-6-烷基(芳基)-5,6-二氢-2H-吡喃-2,4-二酮的合成及其杀菌活性的研究

以5,6-二氢-6-烷基(芳基)-2H-吡喃-2,4-二酮(1)、芳胺(2)和原甲酸三乙酯进行缩合反应,合成了20个3-芳胺甲烯基-6-烷基(芳基)-5,6-二氢-2H-吡喃-2,4-二酮(3).由于分子内氢键的形成,化合物3由一对构象异构体4和5组成.生物活性初步测定结果表明,这些化合物均有一定的杀菌活性.     

微波辐射下蒙脱土K10固载氯化铁氧化二芳基乙醇酮

微波辐射下以蒙脱土K-10固载氯化铁为氧化剂, 氧化二芳基乙醇酮生成二芳基乙二酮化合物, 反应时间短, 产率高, 操作简便, 污染小, 是一种有效的由二芳基乙醇酮氧化制备二芳基乙二酮的方法.     

3—芳胺甲烯基—6—烷基（芳基）_5,6—二氢—2H—吡喃—2,4—二 …

以５,６－二氢－６－烷基（芳基）－２Ｈ－吡喃－２,４－二酮（１）、芳胺（２）和原甲酸三乙酸进行缩合反应、合成了２０个３－芳胺甲烯基－６－烷基（芳基）－５,６－二 喃－２,４－二酮（３）,由于分子内氢键的合成,化合物３由一对构象异构体４和５组成,生物活性初步测定结果表明,这些化合物均有一定的杀菌活性。     

镍催化芳基三氟甲磺酸酯对醛的加成反应及偶联反应

对芳基三氟甲磺酸酯对醛的加成或偶联反应进行了研究.以Ni(dppe)Br_2为催化剂,在锌粉存在下,芳基三氟甲磺酸酯与醛在甲醇溶剂中发生加成反应,在四氢呋喃中发生偶联反应,分别以中等到良好的收率获得芳基甲醇化合物或芳基甲酮化合物.     

1-烷基-4,6-二芳基四氢三嗪硫酮化合物的合成及其氧化反应

三芳基缩二胺与烷基硫脲在二氧六环回流条件下反应, 可生成1-烷基-4,6-二芳基四氢三嗪硫酮化合物3。利用芳香醛, 烷基硫脲和醋酸铵一锅法也能得到3, 而三芳基缩二胺与芳基硫脲反应, 则生成了咪唑啉的硫氰酸盐。室温下,在相转移催化剂TEBA存在时, 3可被高锰酸钾氧化, 得到1-烷基-4,6-二芳基-2(1H)三嗪酮化合物。     

芳基咪唑并[4,5-f][1,10]菲咯啉的无溶剂绿色合成研究

以菲咯啉二酮、苯甲醛及其衍生物和醋酸铵为原料,采用无溶剂绿色研磨工艺,合成了芳基咪唑并菲咯啉化合物.通过对不同反应条件的筛选,得到一条高效、简便、绿色的合成芳基咪唑并菲咯啉化合物路线,不同的芳醛与菲咯啉二酮都可以较高的收率得到相应的芳基咪唑并[4,5-f][1,10]菲咯啉.     

手性γ,γ-偕二芳基羰基化合物的催化不对称合成

正手性γ,γ-偕二芳基羰基化合物及其衍生物广泛存在于天然产物和药物分子中,如鬼臼毒素,Cladosporol和抗抑郁药舍曲林等.通常,手性γ,γ-偕二芳基羰基化合物的合成是以手性化合物为起始原料,通过催化不对称方式来构建这一关键骨架一直是一个挑战性的课题.铑催化芳基硼酸对芳基缺电子烯烃的不对称共轭加成是目前合成手性谐二芳基化合物有效途径之一.利用该策略,选用γ-芳基-β,γ-不饱和酮酸酯(或酮酰胺)类为底物,可能是实现手性γ,γ-偕二     

2－甲基－3－芳基－7－（5，5－二甲基－3－酮－1－环己烯－1－基）甲酸酯－4（3H）－喹唑啉酮的合成

以2－氨基对苯二甲酸（1）为起始原料，与乙酸酐缩合生成7－羧基乙酰苯邻 甲内酰胺（2）；2和芳胺缩合产生7－羧基－2－甲基－3－芳基－4（3H）－喹唑啉 酮（3）；3和N，N－双环己基碳双亚胺（DCC）加成得到中间体4，4在4－二甲氨基 吡啶（DMAP）催化下和5，5－二甲基－1，3－环己二酮（5）缩合得到目标产物2－ 甲基－3－芳基－7－（5，5－二甲基－3－酮－1－环己烯－1－基）甲酸酯－4（ 3H）－喹唑啉酮（6）。所得15个新型化合物的结构均经^1H NMR、元素分析确证， 部分化合物经IC／MSD确证。     

微波辐射下一步合成2-芳基-4，5-二苯基咪唑衍生物

微波辐射下一步合成2-芳基-4;5-二苯基咪唑衍生物;芳基咪唑; 二苯基二（甲）酮; 芳醛; 微波辐射; 合成     

一类环丙烷螺环化合物的简易合成和结构表征

以乙二醇二甲醚为溶剂,在K2CO3及痕量水存在下,鉮盐和多取代贫电子烯烃反应,高立体选择性合成了顺-1-甲氧羰基-2-取代芳基-6-环己烷基-5,7-二氧杂螺-〔2,3〕-4,8-二酮。采用IR、MS、1H NMR、13C NMR、DEPT及二维核磁共振技术对所合成的化合物进行了结构表征,并以NOESY实验确定了该化合物为顺式结构的环丙烷衍生物。     

钯催化苄基氯衍生物、三丁基烯丙基锡和一氧化碳三组分偶联反应:α,β-不饱和酮的有效合成

研究了苄基氯衍生物、CO和三丁基烯丙基锡在零价钯催化剂(Pd(PPh3)4)存在下的反应,结果表明,可有效发生三组分偶联反应,生成不饱和酮化合物.再经碱性氧化铝柱提纯后,转化为α,β-不饱和酮化合物6a～6n,其中,6b,6d～6h,6j,5l和6l～6n等未见文献报道,其结构经红外光谱、1H和13C核磁共振以及高分辨质谱表征确定.     

Synthesis and study of mesogenic compounds having a methylene ketone (-CH2-CO-) linking group

Abstract

Recently we have reported isoflavone derivatives as potential mesogens [1]. During the synthesis of isoflavone derivatives, 2,4-dihydroxyphenyl benzyl ketone was synthesized as an intermediate. Nguyen Huu Tinh et al. [2] have reported the effect of the influence of the central linkage, such as ethylene, methylene ketone and ketone on the mesogenic compounds. Vora et al. [3] have also reported a mesogenic homologous series with terminal and lateral phenolic groups. To understand the effect of hydrogen bonding originating between methylene ketone and free lateral hydroxy groups, ortho to the methylene ketone group, on mesogenicity, the present homologous series of 2-hydroxy, 4(4′-n-alkoxybenzoyloxy)phenyl benzyl ketone was synthesized. The synthesized compounds were characterized by elemental analysis and spectroscopic techniques. The first six homologues of the present series are non-mesogenic and mesomorphism appears from the heptyl derivative onwards. The present series shows a monotropic smectic A phase except for the last member (octadecyloxy) which exhibits an enantiotropic smectic A mesophase. The transition temperatures are also identified using DSC. The fluorescent studies of some of the compounds of the present series are under investigation.     

环丙基甲基酮的合成研究进展

环丙基甲基酮是合成环丙氟哌酸类广谱抗菌药物和抗艾滋特效药依法韦仑的重要中间体,在医药、化工及农林等领域均有广泛应用。环丙基甲基酮的合成方法大致分为4类,分别以酮类、酯类、醇类及呋喃有机物为原料,在一定条件下生成环丙基甲基酮粗品,经萃取及精馏得到环丙基甲基酮纯品。本文综述了环丙基甲基酮的合成研究进展。     

Vanadium(V)‐Induced Oxidative Cross‐Coupling of Various Boron and Silyl Enolates

Intermolecular oxidative cross‐coupling of two different enolates is one of the most useful reactions to synthesize unsymmetrical 1,4‐dicarbonyl compounds. In this study, the oxovanadium(V)‐induced intermolecular oxidative cross‐coupling of enolates afforded unsymmetrical 1,4‐dicarbonyl compounds. Various boron and silyl enolates underwent the formation of ketone–ester, ester–ketone, ester–ester, amide–ketone and amide–ester coupling products . These results clearly show the versatility of the present oxidative cross‐coupling protocol.     

Aza-Reformatsky-type reaction of alpha-iodomethyl ketone O-alkyl oximes promoted by titanium tetraiodide

Titanium tetraiodide promotes an aza-Reformatsky-type reaction of alpha-iodomethyl ketone O-alkyl oximes with carbonyl compounds to give beta-hydroxy ketone O-alkyl oximes in good to high yields.     

含硅二烃基锡化合物对醇醛(酮)缩合反应的催化活性

考察了10种含硅二烃基锡化合物对柠檬醛与乙二醇及环己酮与乙二醇的缩合反应的催化活性。 研究了催化剂用量、反应时间、醛醇及酮醇的物质的量之比和溶剂等对反应产率的影响。 结果表明,除一种催化剂外,9种化合物对缩醛和缩酮反应均有良好的催化活性,当催化剂用量为反应物质量分数的1.4%,醛与乙二醇的物质量之比为1∶1.3,酮与乙二醇的物质量之比为1∶1.6,以环己烷为带水剂,回流反应3 h,产物收率分别达92%和86%以上。     

Steric effects in conjugated systems : Part V. methylvinyl ketone and methyl-β-N,N-dimethylaminovinyl ketone

Based on the earlier results on methylated butadienes and acroleins, the conformational analysis of methylvinyl ketone was performed using the Wiberg method. The effect of nonbonded interactions involving the methyl group on the molecular geometry was estimated. In agreement with experimental findings the larger amount of the s-cis than s-trans conformer in methylvinyl ketone vs. acrolein is thought to be due to steric hindrance. Contrary to the situation for other unsaturated compounds, the rotation of the methyl group in the s-trans conformer of methylvinyl ketone seems to be determined mainly by nonbonded interactions. The barrier to internal rotation of the methyl group in the s-cis compared to the s-trans conformation seems to be considerably less. The present analysis of the steric properties of methylvinyl ketone seems to indicate that the spectral arguments in favour of nonplanarity of β-N,N-dimethylaminovinyl ketone are equivocal.     

An efficient synthesis of cyclopropyl silyl ketones

The reaction of silylcyclopropyl bromides with dichloromethyl methyl ether in the presence of n-butyllithium is investigated. Under basic reaction conditions, the corresponding cyclopropylidene derivatives are exclusively obtained. The resulting cyclopropylidene compounds are subjected to protonolysis or trapping with electrophiles in a one-pot to give the cyclopropyl silyl ketone derivatives in good yields. Acidic treatment of derived cyclopropyl silyl ketone allows isomerization to give the thermodynamically favorable trans form exclusively.     

Formation of Aldehyde and Ketone Compounds during Production and Storage of Milk Powder

Certain aldehyde and ketone compounds can be used as indicators, at a molecular level, of the oxidized flavor of milk powder instead of sensory evaluation. This study investigated the formation of aldehyde and ketone compounds as affected by the heat-related processing and storage of milk powder. The compounds were extracted by solid phase microextraction fiber and determined using gas chromatography-mass spectrometry. In the results, higher contents of hexanal, 2-heptanone, octanal and 3-octen-2-one were detected in concentrated milk and fresh milk powders than in raw milk and heated milk. The levels of these compounds increased with increasing time of storage of milk powder. Meanwhile, the DPPH radical scavenging activity decreased and peroxide value increased during the production and storage of milk powder. In addition, the pore volume distribution of milk powder particle was determined by nitrogen isotherm adsorption. The porosity of milk powder was significantly correlated to the changes of aldehyde and ketone compounds during storages periods of 3 months (r > 0.689, p < 0.05) and 6 months (r > 0.806, p < 0.01). Therefore attention should be paid to the detectable aldehyde and ketone molecules to control the oxidized flavor, which was influenced by pre-heating as well as concentration and drying during milk powder production.     

Coulometric generation of hydrogen ions by oxidation of mercury in methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone

Mercury(II)-chloride reacts with anhydrous methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone in a precise stoichiometry ratio (1:2), and weakly ionized compounds of mercury with ketones are formed and equivalent quantity of HCl is released. The application of a mercury anode for the quantitative generation of H⁺ ions in 0.25 M sodium perchlorate in anhydrous methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone has been investigated. Current/potentials curves for the solvents, titrated bases, indicator and mercury showed that in these solvents mercury is oxidized at potentials much more negative than those for the titrated bases and other components present in the solution. The protons generated in this way have been used for the titration of some organic bases, with either visual or potentiometric end-point detection. The oxidation of mercury in methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone and the reaction of mercury ions with these solvents have been found to proceed with 100% current efficiency.