共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
N,S-缩烯酮是一类重要的有机合成中间体,其官能团的多样性决定了反应的多样性。N,S-缩烯酮的主要反应有与亲核体的共轭加成、与金属有机试剂的选择性加成、环合(五元环或六元环)、还原和缩合等反应,其在杂环合成中具有非常重要的意义。本文主要综述了N,S-缩烯酮的制备及其在参与合成含氮杂环(吡咯、吲哚、吡啶、嘧啶等)、含氧杂环(呋喃、吡喃等)及在多组分反应中的应用,重点介绍了各类反应的普适性、反应机理或衍生化的研究结果,以更好地认识N,S-缩烯酮分子,并期望通过N,S-缩烯酮实现选择性的合成各类所需的杂环化合物,以促进N,S-缩烯酮在杂环合成中的应用。此外,N,S-缩烯酮合成的杂环化合物大部分具有潜在的生物活性,这将促进其在药物化学及药物合成领域的应用和发展。 相似文献
3.
4.
5.
由氰基乙酸酯或丙二腈先制得氰基取代的烯酮缩硫醇, 然后与二胺反应合成了氰基取代的含杂环烯酮缩胺, 测定了它们的UV、IR、^1H及^1^3C NMR等波谱, 并测定了其中两个化合物的晶体结构, 对所得的波谱和结构特性进行了讨论。 相似文献
6.
氮杂环丁烷类化合物是一类重要的饱和四元含氮杂环化合物,不仅是有机合成中的重要原料、中间体及手性助剂或催化剂,也是氨基酸、生物碱及其天然和合成生物活性或药物活性化合物等分子结构中的重要活性单元。因此,发展氮杂环丁烷结构的合成方法非常重要。本文综述了氮杂环丁烷类化合物合成的发展,着重综述了近十年来该类化合物合成方法的进展,主要包括形成C-N键成环、形成C-C键成环、胺催化的亚胺和丙二烯甲酸酯环加成、亚胺和烯烃的光环加成、缩环扩环重排和氮杂环丁-2-酮(β-内酰胺)还原等方法构建氮杂环丁烷结构的新成果。 相似文献
7.
8.
9.
10.
11.
Kinetics of base hydrolysis of some new heterocyclic azomethines derived from aminotriazol and aromatic aldehydes were investigated in the presence of NaOH in 60% (wt/wt) water-ethanol medium. The base hydrolysis of these Schiff bases is strictly first-order with respect to OH? and Schiff. The rate-determining step is suggested to be the attack of the hydroxide ion on the free base. Effect of the molecular structure of both aldehydes and amines and the nature of organic hydroxylic solvent on the hydrolysis rate was investigated and discussed. 相似文献
13.
The stereoselective synthesis of O-maltosides by reacting benzoyl-substituted heterocyclic ketene aminals 1 or 2 with acetylated maltosyl bromide 3 was investigated.Compounds 1 or 2 reacted with 3 in the presence of mercuric cyanide to give O-maltosides 4 or 5 with E-configuration.While 1 reacted with 3 in the presence of calcium hydride to give O-maltosides 6 with Zconfiguration. 相似文献
14.
Described in this work is a catalyst-free, in most cases neat, preparation of heterocyclic thienyl sulfides. This method utilizes 2-thiophenethiol and various activated halogenated heterocycles in a substitution-type reaction to form an interesting array of sulfides. Yields obtained are comparable to other published methods, and the reaction requires milder conditions, has shorter reaction times, and most times eliminates the need for column chromatography during workup. 相似文献
15.
16.
T. K. Venkatachalam 《合成通讯》2013,43(20):3667-3675
Heterocyclic thioureas having multiple substitutions were prepared in two steps with overall yields of 60–80%. Condensation of a substituted heterocyclic amine with thiocarbonyldiimidazole, followed by treatment with a disubstituted phenylethylamine in dimethyl formamide (DMF), yielded the desired heterocyclic thioureas as crystalline solids. 相似文献
17.
18.
Asweknow,carbohydratesplayanimportantroleinnature,especiaIlyasrecogniti0ndeterminantinhost-pathogeninteractionsorinceIl-cellinteractions.Theref0re,stereo-controlledglucosylationhasbecomeone0ftheimportantt0picsinorganicsynthesis]'2.HeterocyclicketeneaminaIsareimportantintermediatesforthesynthesis0fawidevarietyofnewheterocyclesandfusedheterocycles,someofwhichhavehighbiologicalactivity'.IthasbeenrepoFtedthatbenzoyl-substitutedheterocyclicketeneaminalscanreactwith2usingmercuriccyanideascatalystt… 相似文献
19.
本文介绍了应用液-液催化、氢-氚交换法制备某些氚标记杂环化合物。采用PtO_2作为催化剂,选用含有杂氮原子的、杂氮和杂硫原子的、杂氧原子的十二种化合物作为研究对象,并用~3H NMR研究了氚在这些杂环化合物中的位置以及它在分于中的相对丰度,得到了满意的氚渗入结果。 相似文献