共查询到20条相似文献,搜索用时 62 毫秒
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制备了碱性离子液体1,1'-(丁烷-1,4-二基)双(1,4-二氮杂二环[2.2.2]辛烷-1-ium)羟化物,并采用红外光谱、1H核磁共振谱和pH值分析对其进行了表征.然后将它用于室温研磨条件下高效催化合成吡喃酮[2,3-d]嘧啶酮和[2,3-d]嘧啶.该法步骤简单,反应时间短,产物收率高,无需柱色谱分离,原料易得,且可回收利用. 相似文献
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研究了6-溴-N-[3-氯-4-(3-氟苄氧基)苯基]噻吩[2,3-d]并嘧啶-4-胺的合成新方法.以相对廉价的2,5-二羟基-1,4-二噻烷和丙二腈为原料,依次通过Gewald反应、芳环溴代、缩合、环合以及Dimroth重排四步反应得到目标产物6-溴-N-[3-氯-4-(3-氟苄氧基)苯基]噻吩[2,3-d]并嘧啶-4-胺,总产率为56.9%.用1H NMR,IR,MS和HRMS对产物进行了结构表征.并应用该方法,合成了一系列的6-溴-N-芳基噻吩[2,3-d]并嘧啶-4-胺类化合物.研究表明该方法具有原料易得、操作简便、收率较高,且产物容易分离纯化等优点. 相似文献
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The condensation of 2-amino- and 2-methylthio-4, 6-dihydroxypyrimidines and barbituric and thiobarbituric acids with -diketones in strong acids leads to pyrylia[2,3-d]pyrimidine salts, which on treatment with ammonia or aniline are converted to pyrido[2,3-d]pyrimidines or to 8-phenylpyrido[2,3-d]pyrimidinium salts, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1484–1486, November, 1977. 相似文献
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I. V. Smolanka S. M. Khripak A. A. Zeikan' A. A. Dobosh 《Chemistry of Heterocyclic Compounds》1977,13(6):609-610
Intramolecular cyclization of 2-(N-acylselenoureido)-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]thiophenes in alkaline media leads to the formation of the potassium salt (I) of 2-seleno-4-oxo-3,4,5,6,7,8-hexahydrobenzo[b]thieno[2,3-d]pyrimidine, acidification of which yielded the corresponding base in free form. Some pyrimidine compounds containing a selenium atom in the side chain were obtained by reaction of potassium salt I with halo derivatives (ClCH2CH2COOCH3 and ClCH2CH2OH).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 753–754, June, 1977. 相似文献
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É. É. Grinshtein É. I. Stankevich G. Ya. Dubur 《Chemistry of Heterocyclic Compounds》1972,8(3):386-389
The mutual condensation of 4-aminouracil or 2,4-diamino-6-hydroxypyrimidine with bisacetonitrile and aldehydes was used to synthesize 2,4-dioxo-5-R-7-methyl-6-cyano-1,2,3,4,5,8-hexahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine derivatives, which were oxidized with chromic anhydride to the corresponding 2,4-dioxo-5-R-7-inethyl-6-eyano-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4-dihydro[2,3-d]pyrimidines. The IR and UV spectra of the synthesized compounds were recorded.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 422–425, March, 1972. 相似文献
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Two series of 2H-pyrano[2,3-d]pyrimidine-2,5(6H)-dione derivatives have been prepared. Thus, the reaction of 6-hydroxy-pyrimidin-4(3H)-ones (1 a–c) with bis-2,4,6-trichlorphenyl malonates (2 a–d) or diethyl malonates (3 a–d) afforded good yields of 4-hydroxy-2H-pyrano[2,3-d]pyrimidine-2,5(6H)-diones (4 a-l). Application of our modifiedPechmann reaction9–11 using -aminocrotonate (5) or -keto esters (6, 7) in the presence of ammonium acetate yielded the 2H-pyrano[2,3-d]pyrimidinediones8 a–h.Dedicated to Prof. Dr.Karl Schlögl, University of Vienna, on the occasion of his 60th birthday. 相似文献
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Samuel E Watson Farrah Khandkar My Bui Anatoly Markovich Edward C. Taylor 《合成通讯》2013,43(20):3885-3894
A short, succinct route to biologically active and medicinally important pyrrolo[2,3-d]pyrimidines has been developed starting from readily available acyclic aldehydes. A very efficienttwo step sequence involving a Knoevenagel condensation followed by copper mediated 1,4-conjugate of vinyl magnesium bromide sets up the acyclic precursor. Then, guanidine cyclization followed by a palliduim catalyzed amination reaction or ozonolytic cleavage of the vinyl substituent followed by guanidine cyclization and intramolecular imine formation complete the synthesis. 相似文献
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Electrochemical oxidation of 3,4-dihydroxybenzoic acid (1) in the presence of 1,3-dimethylbarbituric acid (2) and 1,3-diethyl-2-thiobarbituric acid (3) as nucleophiles in aqueous solution has been studied using cyclic voltammetry and controlled-potential coulometry. The results indicate that 1 via Michael reaction under electro-decarboxylation reaction converts to benzofuro[2,3-d]pyrimidine derivatives (6a, 6b). The electrochemical synthesis of 6a, 6b has been successfully performed in an undivided cell in good yields and purity. 相似文献