高效液相色谱法测定2-羟基-3-萘甲酸生产废水中相关物质的含量

采用高效液相色谱法测定2 羟基3 萘甲酸生产废水中1 羟基2 萘甲酸、2 羟基3 萘甲酸、2 羟基6 萘甲酸、β萘酚四组分的含量。方法以Selectosil C18 为分离柱,以V甲醇∶V水=80∶为流动相,紫外236 nm波长处检测。回收率为96%~103%,RSD<2.5%。     

4-(7-甲氧基-2,2-二甲基-2,3-二氢苯并呋喃-5-基)-2-芳氨基噻唑的合成、晶体结构与杀虫活性

以2-(2-甲基烯丙氧基)苯酚为原料, 经Claisen重排、呋喃环化、醚化、Friedel-Crafts乙酰化、α-溴代和噻唑环化等反应合成了22种4-(7-甲氧基-2,2-二甲基-2,3-二氢苯并呋喃-5-基)-2-芳氨基噻唑化合物. 化合物的结构经质谱、1H NMR和元素分析等确证. 采用单晶X射线衍射仪测定了化合物7j的晶体结构, 该晶体属于单斜晶系, 空间群为C2/c, 晶胞参数a=2.21140(12) nm, b=0.87602(5) nm, c=2.13911(12) nm, β=115.5380(10)°; V=3.7391(4) nm3, Z=8, Dc=1.375 g/cm3, F(000)=1616, S=1.046, μ=0.333 mm-1, 最终偏差因子R1=0.0390, wR2=0.1079. 杀虫活性实验结果表明, 化合物7a, 7b, 7h和7t在浓度为500 mg/L时对蚕豆蚜死亡率分别为95.12%, 62.60%, 57.53%和59.06%.     

固相微萃取-高效液相色谱法测定水中的酞酸二(2-乙基己基)酯

分别采用PDMS、PDMS／DVB、CWX／DVB三种萃取头,应用固相微萃取与高效液相色谱联用技术(SPME-HPLC)分析了水溶液中的痕量酞酸二(2-乙基已基)酯(DE-HP)。实验发现,PDMS／DVB萃取头的萃取效果较其他两种萃取头理想;对SPME的萃取条件进行了优化,建立了水中痕量DEHP的SPME-HPLC分析方法,并对实际水样进行了分析。该方法的线性范围为0．62～15．60mg／L,相关系数为0．9991,检出限为0．06mg／L(3σ,n=11),相对标准偏差(RSD)为3．3％,回收率为89．9％～101．3％。     

5-甲氧基-2-苯基-2, 3-二氢苯并呋喃的制备——介绍一个大学综合化学实验

介绍了一个大学综合化学实验。该实验以对甲氧基苯酚和苯乙烯为原料,六氟异丙醇为溶剂,2,3-二氯-5,6-二氰基-1,4-苯醌为氧化剂,室温合成5-甲氧基-2-苯基-2,3-二氢苯并呋喃,并用IR、1H NMR、13C NMR和HRMS对产物结构进行表征。本实验有益于激发学生的科研兴趣和探索精神,训练学生的综合实验操作技能和分析能力,培养学生的创新思维和科研能力。     

高效液相色谱法测定过氧化氢工作液中2-乙基蒽醌、2-戊基蒽醌及其氢化物

建立高效液相色谱法快速测定过氧化氢工作液中2-乙基蒽醌、2-戊基蒽醌及其氢化物含量的方法.选择ZorbaxXDB–C18色谱柱(250 mm×4.6 mm,5μm)为分离柱,以甲醇–水溶液(体积比为75:25)为流动相,流量为0.8 mL/min,柱温为40℃,紫外检测器检测,检测波长为254 nm,外标法定量.2-乙...     

2-乙基-4-羟基-5-甲基-3(2H)-呋喃酮和2-甲基-4-羟基-5-乙基-3(2H)-呋喃酮互变异构体及其甲氧基衍生物的高效液相色谱分析方法

1　引　　言2 乙基 4 羟基 5 甲基 3( 2Ｈ) 呋喃酮也叫酱油酮 ,是 1 988年才投放市场的新型香料。在结构上与呋喃酮、麦牙酚结构相似。它具有甜的、水果香味 ,主要用于水果、咖啡、面包和烟草的香精配制。酱油酮是天然存在的 ,首先从日本酱油中分离出来 ,后来又从咖啡和甜瓜中分离出来。酱油酮具有一定的酸性 ,是一个极性分子 ,很难从反应体系的水中分离出来。虽然红外光谱 ,紫外光谱 ,核磁共振及质谱都可以用于分析酱油酮 ,但是 ,由于酱油酮具有烯醇式互变异构体 ,ＨＰＬＣ是首选的分离分析方法。酱油酮可以由糖在酶催化下进行生物合成…     

(E)-2,3,3-三甲基-4-甲氧基-5-(3’-甲基-2’-丁烯基)-6-苯乙烯基-2,3-二氢苯并呋喃的合成及机理研究

天然提取的木豆素C与氯代异戊烯反应,生成木豆素C的衍生物2,此衍生物通过克莱森重排和关环反应,得到了一个含五元环的木豆素C的衍生物(E)-2,3,3-三甲基-4-甲氧基-5-(3’-甲基-2’-丁烯基)-6-苯乙烯基-2,3-二氢苯并呋喃。其结构经1H NMR、MS、元素分析和量子计算得到确证,并讨论了可能的重排反应及环化机制。     

2,3-二取代-5-羟基苯并呋喃衍生物的合成

用1,4-环己二酮与联二酮的缩合反应首次合成了4个未见文献报道的标题化合物,结构经IR,1H NMR,MS和元素分析等测试确证,并对反应条件进行了初步探讨.结果表明,以LiCl作为催化剂,用1,3-二甲基-2-咪唑啉酮(DMI)为溶剂,于200℃反应1 h时收率最高.     

4-(7-甲氧基-2,2-二甲基-2,3-二氢苯并呋喃-5-基)-2-苄亚氨基噻唑的合成与生物活性

呋喃酚经醚化、傅克酰化、α-溴代、噻唑环化和亚胺化等反应合成了16种4-(7-甲氧基-2,2-二甲基-2,3-二氢苯并呋喃-5-基)-2-苄亚氨基噻唑新化合物.化合物的结构经1H NMR、质谱和元素分析等确证.杀虫活性实验结果表明,化合物2a和2i在500 mg/L对棉红蜘蛛死亡率分别为53.10%和67.71%,杀菌活性实验结果表明,化合物2a和2k在25 mg/L对油菜菌核病菌抑制率分别为57.9%和59.8%,除草活性实验结果表明,2l在2250 g.ai/ha浓度下对苘麻、刺苋、藜具有一定的除草活性.     

3-（3-乙酰基-5-芳氧亚甲基-2,3-二氢-1,3,4-噁二唑-2-基）色酮类化合物的合成

3-（3-乙酰基-5-芳氧亚甲基-2;3-二氢-1;3;4-噁二唑-2-基）色酮类化合物的合成;噁二唑啉;色酮;合成     

Synthesis and Crystal Structure of （S）-Ethyl-2-（2-methoxy-phenylsulfenamido）-3-（1H-indol-3-yl）propanoate

With an aim to discover novel AHAS inhibitors,the title compound (S)-ethyl-2(2-methoxy-phenylsulfenamido)-3-(1H-indol-3-yl)propanoate (C 21 H 22 N 2 O 4 S,M r=398.47) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis.The crystal belongs to orthorhombic,space group P2 1 2 1 2 1 with a=8.078(2),b=12.824(4),c=18.788(6),V=1946.2(10) 3,Z=4,F(000)=840,D c=1.360 mg/m 3,μ=0.197 mm-1,the final R=0.0433 and wR=0.1035 for 3075 observed reflections with I > 2σ(Ⅰ).The absolute structure Flack parameter X of this compound is 0.00(8).A total of 14375 reflections were collected,of which 3431 were independent (R int=0.0437).X-ray analysis reveals that the crystal structure involves two intermolecular N-H···O and one N-H···S intermolecular hydrogen bonds with the neighboring molecules.The crystal structure was compared with our previously reported (S)-methyl 2-(4-R-phenylsulfonamido)-3-(1H-indol-3-yl)propanoate (R=H(1) and Cl(2)),which provided some useful information of these compounds.     

Synthesis,Crystal Structure and Antitumor Activity of (E)-1-(7-Methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl)-3-(2-methoxyphenyl)-2-(1H-1,2,4-triazol-1-yl)propenol

The title compound,(E)-1-(7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl)-3-(2-methoxyphenyl)-2-(1H-1,2,4-triazol-1-yl)propenol(3a), was synthesized by the Aldol condensation reaction of 1-(7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl)-2-(1,2,4-triazol-1-yl)ethanone with 2-methoxybenzaldehyde and then reduced with NaBH_4, and its crystal structure was determined by single-crystal X-ray diffraction: monoclinic system, space group P21 with a = 6.2002(3), b = 12.8452(7), c = 13.2257(7) ?, Z = 2, V = 1031.23(9) ?~3, M_r = 407.46, Dc = 1.312 Mg/m~3, S = 1.054, μ = 0.091 mm-1, F(000) = 432, the final R = 0.0353 and w R = 0.0769 for 3161 observed reflections(I 2σ(I)). X-ray analysis displays that the title compound adopts an E configuration for the C(7)=C(8) double bond and S configuration for the chirality center with the specific rotation of –63.75°. Furthermore, the stability of the crystal was maintained through the intermolecular hydrogen bond O(1)–H···N(3). The antitumor assay exhibits that the title compound 3a(E configuration) has a good antitumor activity against the Hela cell line with the IC50 value of 36.9 μM, which is better than that of 3b(Z configuration).     

Synthesis of 5-Amino-4-(4-aryl-2-thiazolyl)-2,3-Dihydro-2-Pyrrolones

A method was developed for preparation of 5-amino-4-(4-aryl-2-thiazolyl)-2,3-dihydro-2-pyrrolones by alkylation of 4-aryl-2-thiazolylacetonitriles by N-substituted chloroacetamides in the presence of K₂CO₃. In 1-(1-naphthyl)-substituted pyrrolones atropoisomerism was observed.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 2, 2005, pp. 266–269.Original Russian Text Copyright © 2005 by Resnyanskaya, Tverdokhlebov, Tolmachev, Volovenko.     

Synthesis of 3-(2-(4,5-Dihydro-3,5-diphenylpyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one Derivatives via Multicomponent Approach

An efficient synthesis of 3-(2-(4,5-dihydro-3,5-diphenylpyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one derivatives by a simple, atom-economical, and multicomponent reaction of chalcones, thiosemicarbazide, and 3-(2-bromoacetyl) coumarins in the presence of aqueous sodium hydroxide in refluxing ethanol is reported. The structures of newly prepared compounds have been confirmed by their analytical and spectral (IR, ¹HNMR, ¹³CNMR and mass) data.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Short Synthesis of 1-(3-tert-Butyl-1-phenyl-1H-pyrazol-5-yl)-3-(5-(2-morpholinoethoxy)-2H-chromen-8-yl) Urea Derivatives

A short and efficient synthesis of 1-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-3-(5-(2-morpholinoethoxy)-2H-chromen-8-yl) urea derivatives (1a–c), a novel type of p38 MAPK inhibitors, is described. The Claisen thermal rearrangement of arylpropargyl ethers was employd as a key step to synthesize the chromene core. The solvent effect on the ratio of the resultant two isomers of Claisen thermal rearrangement, namely 2-methylbenzofuran and 2H-chromen, was also investigated.     

Synthesis of 3-[4-(1-Benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one Derivatives as Biological Agents

A protocol for the synthesis of 3-[4-(1-benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one derivatives (5a–e) has been developed from 1-(1-benzofuran-2-yl)-2-bromoethanone (2),which served as a key intermediate for the synthesis of the title compounds. The reaction of compound 2 with thiourea furnished 4-(1-benzofuran-2-yl)-1,3-thiazol-2-amine 3, which upon further reaction with various aromatic aldehydes, gave Schiff bases 4a–e. These Schiff bases, when treated with thioacetic acid in the presence of catalytic amount of anhydrous ZnCl₂, yielded thiazolidinone derivatives 5a–e. All the newly synthesized compounds have been characterized by analytical and spectral data and screened for their antimicrobial and analgesic activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis of 3-(3-Acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones

A method is proposed for the synthesis of 3-(3-acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones which consists of the conversion of 3-formylchromones to aroylhydrazones and their subsequent heterocyclization using acetic anhydride.