正相高效液相色谱法分离和测定2—（4—羟基苯氧基）丙酸

采用在硅胶柱（ＺＯＲＢＡＸ ＳＩＬ）上，以正己烷：乙酸＝７０：３０：２．５为流动相及ＵＶ检测器（２５４ｎｍ）的高效液相色谱法分离和测定２－（４－羟基苯氧基）丙酸。在选定的色谱操作条例上，２－（４－羟基苯氧基）丙酸与杂质对苯二酚等之间具有良好的分离效果。该方法具有较好的重现性和准确性。     

3-(2-氧代环烷基)丙酸与(R)-2-硫代四氢噻唑-4-羧酸乙酯的反应

３－（２－氧代环烷基）丙酸与（Ｒ）－２－硫代四氢噻唑－４－羧酸乙酯的反应李叶芝,田颜清,黄化民（吉林大学化学,长春,１３００２３）关键词（Ｒ）－２－硫代四氢噻唑－４－羧酸乙酯,Ｎ－３－（２－氧代环烷基）丙酰－２－硫代四氢噻唑－４－羧酸乙酯,环合反应,...     

Synthesis of N-Substituted Derivatives of 2-(4-Amino-2-methyl-1H-indol-3-yl)- and 2-(6-Amino-2-methyl-1H-indol-3-yl)acetic Acids

A method was developed for the production of indole compounds containing an amino group at positions 4 and 6 of the benzene ring on the basis of the indolization of the 3-acetylaminophenylhydrazone of ethyl levulinate. A series of derivatives of 2-(4-amino-2-methyl-1H-indol-3-yl)- and 2-(6-amino-2-methyl-1H-indol-3-yl)acetic acids at the 4- and 6-amino group were synthesized.     

Synthesis of 5-[2-(Phenoxy)ethyl] Derivatives of 6-Methyluracil, 6-Methyl-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one,and 2-Imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one

A synthesis of novel derivatives of 6-methyluracil, 6-methyl-2-thioxo-, and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one containing a 2-(phenoxy)ethyl substituent at position 5 of the pyrimidine ring has been carried out. It was found that 5-[2-(phenoxy)ethyl] derivatives of 6-methyl-2-thioxo- and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one are obtained by the condensation of the corresponding ethyl 3-oxo-2-(2-phenoxyethyl)butanoates with thiourea or guanidine. 6-Methyl-5-[2-(phenoxy)ethyl]uracils can be prepared by treating 6-methyl-5-[2-(phenoxy)ethyl]-2-thioxo-2,3-dihydro-1H-pyrimidin-4-ones with an excess of aqueous monochloroacetic acid solution. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1217, August, 2005.     

Synthesis of 1,5-Disubstituted 3-(4-Hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-pyrazolines

A series of 1,5-disubstituted 3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-pyrazolines were synthesized by the reaction of α,β-unsaturated ketones derived from dehydroacetic acid and hydrazine in hot acetic acid or propionic acid. The structures of all new compounds were elucidated by microanalyses, ¹H and ¹³C NMR, IR, and mass spectroscopic measurements.     

Synthesis of 1,5-Disubstituted 3-(4-Hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-pyrazolines

Summary. A series of 1,5-disubstituted 3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-pyrazolines were synthesized by the reaction of α,β-unsaturated ketones derived from dehydroacetic acid and hydrazine in hot acetic acid or propionic acid. The structures of all new compounds were elucidated by microanalyses, ¹H and ¹³C NMR, IR, and mass spectroscopic measurements.     

Syntheses of substituted 1-methyl-2-(1,3,4-thiadiazol-2-yl)-4-nitropyrroles and 1-methyl-2-(1,3,4-oxadiazol-2-yl)-4-nitropyrroles

Starting from readily available ethyl-4-nitropyrrole-2-carboxylate ( 1 ), substituted 1-methyl-2-(1,3,4-thiadiazol-2-yl)-4-nitropyrroles and 1-methyl-2-(1,3,4-oxadiazol-2-yl)-4-nitropyrroles were prepared. The reaction of 1 with diazomethane gave ethyl 1-methyl-4-nitropyrrole-2-carboxylate ( 2 ). Reaction of compound 2 with hydrazine hydrate afforded the corresponding hydrazide 3 . The reaction of 3 with formic acid yielded 1-(1-methyl-4-nitropyrrole-2-carboxyl)-2-(formyl)hydrazine ( 7 ). Refluxing of the latter with phosphorus pentasulfide in xylene yielded compound 6 in 40% yield. Reaction of compound 7 with phosphorus pentoxide afforded compound 9 . Reaction of compound 3 with 1,1′-carboxyldiimidazole in the presence of triethylamine yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-oxadiazoline-4(H)-5-one ( 11 ). Refluxing compound 3 with cyanogen bromide in methanol gave compound 12 . Compound 13 could be obtained through the reaction of compound 3 with carbon disulfide in basic medium. Alkylation of compound 13 afforded the correspanding alkylthio derivative 14 . Reaction of 1-methyl-4-nitropyrrole-2-carboxylic acid ( 15 ) with thiosemicarbazide and phosphorus oxychloride gave 2-amino-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 16 ). Sandmeyer reaction of compound 16 yielded 2-chloro-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 17 ). Refluxing of the latter with thiourea afforded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazoline-4(H)-5-thione ( 18 ). Alkylation of compound 18 gave the corresponding alkylthio derivative 19 . Oxidation of the latter with hydrogen peroxide in acetic acid yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-5-methylsulfonyl-1,3,4-thiadiazole ( 20 ).     

Deblocking of o-Nitrophenylsulfenyl-Protected Peptides by Ammonium Thiocyanate and (2-Methyl-1-indolyl)acetic acid

The thiocyanate cleavage of the N^a-o-nitrophenylsulfenyl group from peptides in solution or on a solid support proceeds effectively in the presence of (2-methyl-1-indolyl)acetic acid. This scavenger was prepared from 2-methylindole and sodium bromoacetate; it can readily be removed by extraction with base after the cleavage reaction, together with (2-methyl-3-(2-nitrophenylthio)-1-indolyl)acetic acid.     

除草剂2-甲基-4-氯苯氧乙酸(MCPA)与OH自由基的气相化学反应

采用长光程气体池结合傅里叶变换红外光谱仪测得了除草剂2-甲基|4|氯苯氧乙酸(MCPA)与·OH自由基在23 ℃时的反应速率常数为2.67×10-11  cm3/(s*mol), 以此估算了在大气中·OH自由基浓度为 7×105  mol/cm3时, MCPA与·OH自由基反应导致的大气寿命为14.9 h. 结果表明, 在大气环境中MCPA较容易降解, 不会通过大气输送对环境造成广泛和持久性污染.      

4(3H)-喹唑啉酮类Schiff碱的合成与抗烟草花叶病毒活性

采用邻氨基苯甲酸经醋酐酰化闭环得2-甲基苯并噁嗪-4-酮, 水合肼回流合成2-甲基-3-氨基-4(3H)-喹唑啉酮, 在无水乙醇中与芳醛反应得4(3H)-喹唑啉酮类Schiff碱. 经元素分析, IR, 1H NMR, 13C NMR对所合成的化合物进行了结构确认和表征. 初步生物活性测试表明, 化合物3t具有较高的抗烟草花叶病毒活性.     

3-(N-取代苯基-2-乙酰胺基)硫基-4-N-取代邻羟苯基亚胺基-5-甲基-1,2,4-三唑类化合物的合成及生物活性研究

以对称二氨基硫脲为原料,与冰醋酸反应生成5-甲基-4-氨基-1,2,4-三唑-3-硫酮(1);在弱酸性条件下,1与取代水杨醛反应生成席夫碱中间体5-甲基-4-(N-取代邻羟苯基)亚胺基-1,2,4-三唑-3-硫酮(2a～2c);最后在碱性条件下分别与N-取代苯基-2-氯乙酰胺发生烷基化反应生成15种未见报道的目标化合物3-(N-取代苯基-2-乙酰胺基)硫基-4-(N-取代邻羟苯基)亚胺基-5-甲基-1,2,4-三唑(3a～3o),其结构经IR,1H NMR,13C NMR确证.初步生物测试表明,质量分数为0.01%时,3a～3o对白色念珠菌的抑菌率均达90%以上,具有很强的抑菌活性;对金黄色葡萄球菌、大肠杆菌的抑菌率达80%以上,具有较强的抑菌活性.     

Synthesis of 3-Hydroxy-6-Methyl- and 3-Hydroxy-2-(2-phenylethyl)pyridines and Their Sulfur-Containing Amino and Hydroxymethyl Derivatives

The aminomethylation of 3-hydroxy-6-methyl- and 3-hydroxy-2-(2-phenylethyl)pyridines by secondary amines has been investigated. It was shown that like 2-alkyl-3-hydroxypyridine aminomethylation is directed primarily to position 6 and then 4 of the pyridine ring. On heating the aminomethyl derivatives of 3-hydroxy-6-methyl- and 3-hydroxy-2-(2-phenylethyl)pyridines with acetic anhydride the corresponding acetoxy derivatives were obtained, which were converted on heating with hydrochloric or hydrobromic acids into hydroxy and bromomethyl derivatives. Isothioureidomethyl and benzimidazolylthiomethyl derivatives were synthesized by heating the bromomethyl-substituted derivative with thiourea or with 2-mercaptobenzimidazole. The structures of compounds were confirmed by data of ¹H NMR spectra. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1189–1194, August, 2005.     

Bildung von 2-(1-Methyl-1, 4, 5, 6-tetrahydropyridyl-3)-2-oxazolin-4-on aus 1-Methyl-1, 4, 5, 6-tetrahydronicotinsäureamid und Bromessigsäureäthylester und seine Überführung in O-(1-Methylnipecotinoyl)glykolsäureamid via das dazu tautomere Cyclol

The main product of the reaction between 1-methyl-1, 4, 5, 6-tetrahydronicotin-amide and ethyl bromoacetate is shown to be the 2-(1-methyl-1, 4, 5, 6-tetrahydropyridyl-3)-2-oxazoline-4-one which on partial hydrogenation followed by reaction with alkali affords O-(1-methylnipecotinoyl)glycolic amide, presumably via the tautomeric cyclol.     

Enantioselektive α-Alkylierung von Asparagin- und Glutaminsäure über die Dilithium-enolatocarboxylate von 2-[3-Benzoyl-2-(tert-butyl)-1-methyl-5-oxoimidazolidin-4-yl]essigsäure und 3-[3-Benzoyl-2-(tert-butyl)-1-methyl-5-oxoimidazolidin-4-yl]propionsäure

Overall Enantioselective α-Alkylation of Aspartic and Glutamic Acid through Dilithium Enolatocarboxylates of 2- [3-Benzoyl-2-(tert-butyl)-1-methyl-5-oxoimidazolidin-4-yl]acetic and 3-[3-Benzoyl-2-(tert-butyl)-1-methyl-5-oxoimidazolidin-4-yl]propionic Acid, respectively The pure methyl esters 10 of the heterocyclic carboxylic acids specified in the title were prepared in several steps by known methods from aspartic and glutamic acid, with overall yields of ca. 20%. The corresponding heterocyclic acids 11 were doubly deprotonated by LiNEt₂/BuLi or LiN(i-Pr)₂/BuLi to give enolatocarboxylates ( 3 ). The latter were reacted with electrophiles (MeOD, Mel, C₆H₅CH₂Br) to give the crystalline products 14 – 21 diastereoselectively. Hydrolysis of the imidazolidinone ring of three such products gave the corresponding α-branched aspartic and glutamic acids 22 – 24 of known absolute configuration, thus establishing the stereochemical course of the overall enantioselective alkylations.     

Synthesis and transformations of 2- and 4-(2-Methylquinolin-4-ylamino)benzoic acids and ethyl 4-(2-methylquinolin-4-ylamino)benzoates and their fluorescent properties

2- and 4-(2-Methylquinolin-4-ylamino)benzoic acids and ethyl 4-(2-methylquinolin-4-ylamino)-benzoates having a substituent in the 6(8)-position of the quinoline ring were synthesized by reaction of the corresponding substituted 4-chloro-2-methylquinolines with 2- and 4-aminobenzoic acids and ethyl 4-aminobenzoate. Intramolecular cyclization of 2-(2-methylquinolin-4-ylamino)benzoic acids in concentrated sulfuric acid gave 7-hydroxy-6-methyldibenzo[b,h][1,6]naphthyridines, and ethyl 4-(2-methylquinolin-4-ylamino)benzoates were converted into 4-(2-methylquinolin-4-ylamino)benzoic acids by alkaline hydrolysis.     

Novel,Simple, and Efficient Synthesis of 3-(2-(5-(Benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one Derivatives via a One-Pot,Four-Component Condensation Reaction

The synthesis of 3-(2-(5-(benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one derivatives was achieved through a one-pot, four-component reaction involving condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, thiosemicarbazide, phenacylcyanaide, and various aryl aldehydes in dry alcohol and few drops of acetic acid under reflux condition. This four-component reaction has some advantages such as ease of handling, good yields, and easy workup. All structures of newly prepared compounds were confirmed by analytical and spectral data.     

Synthesis of 2,5 -Bis(4-methyl-2-thienyl)thiophene and 2,5-Bis(4-methyl-2-thienyl)pyrrole

Syntheses of 2,5-bis(4-methyl-2-thienyl)thiophene 3 and 2,5-bis(4-methyl-2-thienyl)pyrrole 4 are described. The key step involves Stetter reaction between 4-methyl-2-thiophenecarboxaldehyde and divinyl sulfone. Cyclizaton of the resulting 1,4-bis-(4-methyl-2-thienyl)-1,4-butanedione 2 with Lawesson's reagent gives 2,5-bis(4-methyl-2-thienyl)thiophene 3, whereas condensation with ammonium acetate provides the 2,5-bis(4-methyl-2-thienyl)pyrrole 4.     

Synthesis of 2-(Pyrazol-1-yl)pyrimidine Derivatives by Cyclocondensation of Ethyl Acetoacetate (6-Methyl-4-oxo-3,4-dihydropyrimidin-2-yl)hydrazone with Aromatic Aldehydes

2-(4-Arylidene-3-methyl-5-oxo-4,5-dihydropyrazol-1-yl)-6-methylpyrimidin-4(3H)-ones were obtained by reaction of ethyl acetoacetate (6-methyl-4-oxo-3,4-dihydropyrimidin-2-yl)hydrazone with aromatic aldehydes. Successful cyclization occurs with aldehydes containing an auxochromic substituent in the para position.     

Synthesis of Derivatives of 4-Hydroxy-2-methyl-3-[2-(5-mercapto-1H-1,2,4-triazol-3-yl)ethyl]quinoline and 2-[2-(4-Hydroxy-2-methyl-3-quinolyl)ethyl]-4H-3,1-benzoxazin-4-one

From 4-hydroxy-2-methylquinoline-3-propionyl chlorides hydrochlorides the corresponding thiosemicarbazides were synthesized. The cyclization of the latter both in alkaline and acidic media furnished 4-hydroxy-2-methyl-3-[2-(5-mercapto-1H-1,2,4-triazol-3-yl)ethyl]quinolines. The reaction of the above propionyl chlorides with anthranilic acid afforded the corresponding 2-[2-(4-hydroxy-2-methyl-3-quinolyl)ethyl]-4H-3,1-benzoxazin-4-ones.     

2-(2-氯乙氧基)乙酸酯的合成及性质

在探索 2 氧代 1 ,4 二氧六环应用的实验中 ,我们发现利用 2 氧代 1 ,4 二氧六环与氯化亚砜及一些低碳醇反应 ,可以使 2 氧代 1 ,4 二氧六环发生开环反应 ,生成一类新的有机氯代醚酯类化合物——— 2 ( 2 氯乙氧基 )乙酸酯。其中 ,Ｒ分别为甲基、乙基、丙基、异丙基、丁基和仲丁基。该类化合物在酸性、碱性条件下水解 ,可以得到不同的产物。由于 2 氧代 1 ,4 二氧六环可由一缩二乙二醇经催化脱氢得到[1 ] ,而一缩二乙二醇又是工业上制备乙二醇的副产物。因而开展有关 2 ( 2 氯乙氧基 )乙酸酯的合成及性质方面的研究可为一缩二乙二…