6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪及其共聚物的合成

以6-甲基-3-羟乙基-3,4-2H-1,3-苯并噁嗪(MB-OH)和甲基丙烯酰氯为原料, 通过酯化反应合成了6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪(MBEM). 采用自由基溶液聚合法, 以偶氮二异丁腈(AIBN)为引发剂, 以甲苯为溶剂, 以MBEM与N-苯基马来酰亚胺(NPMI)为单体, 合成了6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪-co-N-苯基马来酰亚胺共聚物[P(MBEM-co-NPMI)]. 分别对MB-OH, MBEM, P(MBEM-co-NPMI)进行加热固化, 得到相应的交联聚合物PMB-OH, PMBEM和P[P(MBEM-co-NPMI)]. 对其结构、分子量和热性能进行了表征. 结果表明, PMB-OH, PMBEM, P[P(MBEM-co-NPMI)]的最大损耗因子tanδ_max对应的玻璃化转变温度(T_g)分别为92, 129和181℃, 最大损耗模量G"_max对应的T_g分别为56, 91和156℃. 在N₂气氛围下, PMB-OH, PMBEM, P[P(MBEM-co-NPMI)]失重5%的温度分别为257, 244和260℃; 失重10%的温度分别为280, 266和284℃; 800℃的残炭率分别为23.2%, 17.8%和14.0%. 表明P[P(MBEM-co-NPMI)]具有优异的耐热性能.     

Synthesis and Antiradical Activity of 5-Acetyl-2-alkylthio-4-aryl-6-methyl-1,4-dihydropyridine-3-carboxylic Acid Nitriles

The alkylation of 3-cyano-1,4-dihydropyridine-2(3H)-thiones or the condensation of an aromatic aldehyde, cyanothioacetamide, acetylacetone, and methyl iodide in the presence of piperidine has given a series of novel 5-acetyl-2-alkylthio-4-aryl-6-methyl-1,4-dihydropyridine-3-carboxylic acid nitriles. A compound was obtained from 3,5-di(tert-butyl)-4-hydroxybenzaldehyde in the molecule of which were combined the active part of the antioxidant ionol and a 1,4-dihydropyridine ring. It was found that, among the compounds synthesized, the highest antiradical activity occurred in a compound having two hydroxyl groups in the 4-phenyl substituent.     

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.     

3-O-乙酰基熊果酸3-乙酰基-2-[(未)取代苯基]-2,3-二氢-1,3, -噁二唑-5-甲酯的合成及其抗炎活性研究

熊果酸与氯乙酸乙酯反应制得熊果酸乙氧甲酰基甲酯(2), 2与水合肼反应得到熊果酸甲酰肼甲酯(3), 3与羰基化合物反应得到一系列酰腙4a～4g, 再将4a～4g与乙酸酐作用, 环合得到3-O-乙酰基熊果酸3-乙酰基-2-[(未)取代苯基]-2,3-二氢-1,3,4-噁二唑-5-甲酯(5a～5g). 15个新化合物均未见文献报道, 其结构经¹H NMR, IR, MS加以确证, 并进行了药理结果筛选. 结果表明, 部分化合物具有良好的抗炎活性. 其中, 化合物5a (40 mg•kg^－1), 5d (40 mg•kg^－1), 5g (40 mg•kg^－1)与熊果酸相比, 具有更强的疗效.     

2-甲基-6-(3-甲基-2-丁烯基)对苯二醌的合成

以邻甲基苯酚为原料,与1-氯-2-甲基-2-丁烯反应生成2-甲基-6-(3-甲基-2-丁烯基)苯酚,然后催化氧化得到目标产物2-甲基-6-(3-甲基-2-丁烯基)对苯二醌。该合成路线简单,易于操作,最终收率51%。     

Synthesis of 3-Phenyl-6-formyl-3, 4-dihydro-2H-1, 3-benzoxazine

Benzoxazine is a novel class of thermosetting resins, which possesses lots of outstanding properties such as no by-products and near-zero shrinkage during polymerization as well as good molecular design flexibility1-2. Furthermore, polybenzoxazines (PBZs)…     

An expedient synthesis of 3-amino-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one

Racemic 3-amino-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one, 2, was prepared in four steps utilizing a novel mercuric ion assisted ammonia displacement of an N-acyl alkylthioglycine amide 5.     

Synthesis of polyfunctionalized furans from 3-acetyl-1-aryl-2-pentene-1,4-diones

The BF₃-catalyzed cyclization of 3-acetyl-1-aryl-2-pentene-1,4-diones 1a-e in the presence of water in boiling tetrahydrofuran gave bis(3-acetyl-5-aryl-2-furyl)methanes 2a-e in 26-79% yields along with a small amount of 3-acetyl-5-aryl-2-methylfurans 3a-e. The exact structure of 2a was determined by X-ray crystallography. The use of a half volume of the solvent for the reaction of 1a resulted in the formation of 2,4-bis(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-phenylfuran (4) together with 2a and 3a. A similar reaction of 1a was carried out in the presence of 3-acetyl-5-(4-methylphenyl)-2-methylfuran (3d) to afford 4-(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-(4-methylphenyl)-2-methylfuran (5) in 49% yield. The BF₃-catalyzed reaction of 1a with 2,4-pentanedione in dry tetrahydrofuran at 23°C gave 3-(3-acetyl-5-phenyl-2-furfuryl)-4-hydroxy-3-penten-2-one (6a) and 3-(3-acetyl-2-methyl-4-phenyl-5-furyl)-4-hydroxy-3-penten-2-one (7a) in 66 and 24% yields, respectively. The product distribution depended on the reaction temperature. A similar reaction of 1b-e also yielded the corresponding trisubstituted furans 6b-e and tetrasubstituted furans 7b-e in good yields. These results suggested the presence of the furfuryl carbocation intermediate A during the reaction. The one-pot synthesis of 6a and 7a was also achieved by a similar reaction using phenylglyoxal. The deoxygenation of 1a with triphenylphosphine gave 3a in 88% yield, while 1a was treated with concentrated hydrochloric acid to yield 3-acetyl-2-chloromethyl-5-phenylfuran (8) which was quantitatively transformed in ethanol into 3-acetyl-2-ethoxymethyl-5-phenylfuran (9) and in water into 3-acetyl-5-phenylfurfuryl alcohol (10), respectively. In addition, the Diels-Alder reaction of cyclopantadiene with 1a gave the corresponding [4+2] cycloaddition products 11 and 12.     

Synthesis of 1,3-dihydro-5(r)-7,8-ethylenedioxy-2h-1,4-benzo-diazepin-2-ones

1,4-Diazepin-2-ones have been prepared from 1,4-benzodioxine for the first time.M. V. Lomonosov State University, Moscow 119899. Translated from Khimiya Geterotsiklcheskikh Soedinenii, No. 5, pp. 601–607, May, 1994. Original article submitted April 10, 1994.     

Synthesis of 2-Methyl-3-acetyl-5-oxo-5H-[1]benzopyrano[2,3-b]pyridine

For our synthetic work we needed the title compound. Literature survey revealed that 2-amino-4-oxo-4H-[1] benzopyran-3-carboxaldehyde (2-amino-3-formylchro-mone) can undergo condensation with diethyl malonate (or ethyl cyanoacetate) forming ethyl 2-hydroxy(or amino)-5-oxo-5H-[1]benzopyrano[2,3-b]pyridine-3-carboxylate¹.     

A new chemoenzymatic approach to the synthesis of chiral 4-aryl-1,4-dihydro-2H-isoquinolines via the enzymatic resolution of 2-acetyl-4-phenyl-1,4-dihydro-2H-isoquinolin-3-one

A new chemoenzymatic method is proposed for the synthesis of enantiomerically pure 4-phenyl-1,4-dihydro-2H-isoquinolines based on the enzymatic kinetic resolution of 2-acetyl-4-phenyl-1,4-dihydro-2H-isoquinolin-3-one. For the enzymatic resolution of the racemic substrate, readily available ‘home made’ animal liver acetone powders (LAPs) were used. Excellent enantioselectivity, exceeding 500, was achieved in a short reaction time upon application of turkey liver acetone powder as the biocatalyst. Reduction of obtained product led to the formation of amine (R)-1, which is hardly available using standard procedures. These results show that N-acetyl lactams are a new type of substrate for enzymatic biotransformations.     

Synthesis of 2-arylmethylidene-5-oxo-1,4-diphenyl-2,5-dihydro-1H-pyrazol-2-ium-3-olates

Condensation of several arylhydrazones with chlorocarbonyl phenyl ketene gave 2-(arylmethylidene)-5-oxo-1,4-diphenyl-2,5-dihydro-1H-pyrazol-2-ium-3-olates in high yields.     

Synthesis and Reactions of (6-Methyl-2-methylsulfanyl-4-oxo-3,4-dihydro-3-pyrimidinyl)acetyl Azide

Nitrosation of (6-methyl-2-methylsulfanyl-4-oxo-3,4-dihydro-3-pyrimidinyl)acetic acid hydrazide using sodium nitrite in acid medium gave the corresponding azide. Reaction of the latter with alcohols or phenols gave carbamates and with amines gave carbamides.     

Synthesis of New Derivatives of 5-Acetyl-4-hydroxy-2H-1,3-thiazine-2,6(3H)-dione

Russian Journal of Organic Chemistry - 5-Acetyl-4-hydroxy-2H-1,3-thiazine-2,6(3H)-dione reacted with cyclohexyl and benzyl (4-aminophenyl)carbamates in boiling ethanol in the presence of a...