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以2,3-二氢-3-氧代-1,3-苯并(c)-α-吡喃(1)为起始原料, 在氢化钠作用下, 通过与羰基α-氢的Claisen缩合反应, 得到3-乙酰基-2,3-二氢-3-氧代-1,3-苯并(c)-α-吡喃(2), 所得β-二酮与脲、硫脲和脒衍生物分别进行缩合关环, 生成5,6-二氢-5-氧杂-1,3-二氮杂菲衍生物3和4. 在相同的条件下, 吡喃酮1与草酸二乙酯进行缩合反应, 给出3-乙氧乙二酰 基-2,3-二氢-3-氧代-1,3-苯并(c)-α-吡喃(5), 选择3-氨基吡唑、2-氨基咪唑、3-氨基三唑、2-氨基苯并咪唑和3,5-二氨基吡唑-4-偶氮苯与5缩合, 分别环合成5,6-二氢-5-氧杂-1,3-二氮杂菲并和五元含氮杂环衍生物6~10. 所合成的新化合物均经核磁共振光谱、红外光谱及元素分析证明其结构. 相似文献
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以1,6-二氢-6-哒嗪酮-3-甲酰肼(1)与芳香醛反应得到相应的1,6-二氢-6-哒嗪酮-3-羰基芳香醛腙(2a~2e). 再将2a~2e与乙酸酐作用, 合环得到一系列含有1,3,4-噁二唑啉环的衍生物3a~3e; 在DMF中用HSCH2COOH合环, 得到含有4-噻唑烷酮的衍生物4a~4e. 所有化合物的结构均经元素分析, IR, 1H NMR 和MS谱得以证实. 相似文献
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Microwave irradiation was found to efficiently promote the three-component reaction of aromatic aldehyde, thiourea, and vinylbenzene at the presence of TMSCl. The products of 5,6-dihydro-4H-1,3-thiazines were formed in a very short time with good to excellent yields as well as excellent diastereoselectivity. This newly developed protocol provided a much more facile route of preparing functionalized thiazine compounds. [Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental.] 相似文献
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L. Kosychova Z. Stumbreviciute L. Pleckaitiene R. Janciene B. D. Puodziunaite 《Chemistry of Heterocyclic Compounds》2004,40(6):811-815
A one-pot synthetic approach to the novel 5,6-dihydro-4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepines by thermal cyclization of 4-acylhydrazino-2,3-dihydro-1H-1,5-benzodiazepines is described. 相似文献
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Stannic tetrachloride was an efficient Lewis acid catalyst for the aza-acetalization of aromatic aldehydes with o-arylaminomethyl phenols, and a series of novel aryl substituted 3,4-dihydro-2H-1,3-benzoxazines were prepared in good yields under mild conditions. SnCl4 was a more efficient catalyst for the reaction than p-toluenesulfonic acid, sulfuric acid, and aluminium chloride. 相似文献
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V. N. Yarovenko A. V. Shirokov I. V. Zavarzin O. N. Krupinova A. V. Ignatenko M. M. Krayushkin 《Chemistry of Heterocyclic Compounds》2003,39(12):1633-1639
We have developed a method for obtaining derivatives of 4,5-dihydro-1,3,4-thiadiazole-2-carboxamide by acylation of hydrazones of oxamic acid thiohydrazides. Oxidation of the dihydrothiadiazole ring of the indicated products by hydrogen peroxide leads to formation of 2-carbamoyl-4,5-dihydro-1,3,4-thiadiazole 1-oxides. 相似文献
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《化学:亚洲杂志》2017,12(23):3016-3026
In recent years, low‐bandgap polymers have attracted much attention in a wide range of fields. The synthesis of these compounds has been focused on three factors according to the Roncali bandgap theory: 1) the degree of bond‐length alternation (E δr), 2) the aromatic resonance energy of the cycle (E Res), and 3) the substituted groups (E Sub). Herein, we have designed and prepared low‐bandgap polymers in a different way by using the factors E θ (the deviation from planarity of the polymer chain) and E Int (the interaction of the molecular chains in the solid state). Thus, three polycyclic aromatic hydrocarbons with different spatial constructions, based on hexaphenylbenzene derivatives, were prepared in this work: linear ( P1‐OX ), V ( P2‐OX ), and zigzag ( P3‐OX ) types. These well‐defined polymers exhibited interesting optical and electrochemistry behavior due to their different extents of planarity. Matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry gave the incremental orderly molecular weight distributions of P1 , P2 , and P3 , the weight‐average molecular weights ( ) of which were 9000, 5500, and 69 000, respectively. Their lamellar layer structures and π–π intermolecular stacking were demonstrated by using two‐dimensional grazing‐incidence X‐ray diffraction, which revealed the edge‐on chain conformation. Finally, the materials were perfectly adapted to fabricate high‐performance organic field‐effect transistor devices, which revealed that these compounds could have great prospects as semiconductors. 相似文献
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根据苯并吡喃类钾通道开放剂的作用机理和构效关系, 设计合成了13个苯并吡喃-4-异硫脲衍生物, 其结构经IR, 1H NMR, MS和元素分析确证. 大鼠体外血管扩张实验研究表明, 多数化合物在1×10-5 mol•L-1 浓度下对30 mmol•L-1 KCl诱导的大鼠主动脉条收缩具有一定程度的抑制作用, 其中化合物6l的血管收缩抑制活性较强. 相似文献
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Hue T. B. Bui Duy D. Vo Yen N. T. Chau Cuc T. K. Tu Hieu V. Mai Kiet V. Truong 《合成通讯》2013,43(24):2861-2868
A facile synthetic method for the construction of 2-substituted-4-oxo-4H-quinolizine-based core structure has been successfully developed. The synthesis made use of a one-pot Stobbe condensation followed by cyclization starting from the commercially available 2-pyridinecarbaldehyde. The structure of the formed 4-oxo-4H-quinolizine-2-carboxylate was fully confirmed by mass spectra, 1H NMR and 13C NMR, correlation spectrography, heteronuclear multiple bond correlation, and heteronuclear single quantum coherence (HSQC) spectra. The ethyl carboxylate moiety was then further functionalized via direct aminolysis by a range of amines to afford the corresponding 4-oxo-4H-quinolizine-2-carboxamides 4a–i in moderate to good yields. 相似文献
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4-羟基喹啉类[4-hydroxyquinolines或4(1H)quinolones]化合物是一类重要的药物合成中间体,在抗疟、抗癌、抗菌、抗病毒、抗糖尿病等领域发挥重要作用。本文综述了4-羟基喹啉类衍生物的合成方法,包括热环合、碱环合和还原环合等。 相似文献
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异喹啉酮类化合物具有重要药理活性,本文在合成1,2,3,4-四氢-2-苄基异喹啉酮-4衍生物的基础上,参照Hinton方法制备2-异丙基-1,3-二氢-4(1H)异喹啉酮(1),用(1)进一步与芳醛、羟胺、酰氯及苯肼反应得到了相应的衍生物(3a-6e)。 相似文献
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Bao Xiang Hu Zhen Lu Shen Jun Lu Xin Quan Hu Wei Min Mo Nan Sun 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):523-535
The synthesis of some new functionalized thiazolidin-4-one derivatives has been described. The N-substituted-thiosemicarbazides 3a-3i were obtained though the reaction of alkylamines 2a–2i , carbon disulfide, and hydrazine hydrate. The condensation reaction between 3a–3i and 4-amino-2-methanesulfanylpyrimidine-5-carboxaldehyde 1 afforded the thiosemicarbazones 4a–4i . The corresponding thiazolidin-4-ones 5a–5i were prepared by cyclization of 4a–4i with ethyl bromoacetate. The structures of the final products were confirmed by IR, 1 H NMR, 13 C NMR, and HRMS. 相似文献
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