具有生物活性的磷杂环化合物研究: XIV. Lawesson试剂与 含活泼氢的双官能团 化合物的环化反应

研究Lawesson试剂与含活泼氢的双官能团化合物的环化反应,合成了O-P-O,N-P-O,N-P-N型五元、六元及七元磷杂环。探讨了其成环可能性及其环化机理。初步的生物活性测定结果表明,应用Lawesson试剂所合成的磷杂环具有较好的选择性除草活性。     

具有生物活性的磷杂环化合物研究ⅩⅣ.Lawesson试剂与含活泼氢的双官能团化合物的环化反应

研究Lawesson试剂与含活泼氢的双官能团化合物的环化反应,合成了O-P-O,N-P-O,N-P-N型五元、六元及七元磷杂环.探讨了其成环可能性及其环化机理.初步的生物活性测定结果表明,应用Lawesson试剂所合成的磷杂环具有较好的选择性除草活性.     

有机磷杂环化合物研究(Ⅷ)──Lawesson试剂与合两个氨基的底物的成环反应

研究Lawesson试剂与含有两个氨基的底物的成环反应,合成了N-P-N型五元、六元磷杂环3a-3b、sa－5b及8a－8b,并讨论了成环机理．初步的生测结果表明,所合成的磷杂环具有一定的除草活性,因此LR的成环反应是合成具有生物活性的磷杂环的新方法．     

Japanese试剂的环化反应

利用Japanese试剂与含活泼氢的双官能团化合物的环化反应,合成了含N-P-N,N-P-O的五元磷杂环化合物,并用IR,NMR和MS对新化合物进行了表征。     

1,3,2-硫氮磷杂环戊-4-硫酮-2-硫代类化合物的合成和生物活性研究

利用Lawesson试剂与α－氯代乙酰胺类化合物的环缩合及硫化反应合成了10个结构新颖的标题化合物,经IR,1HNMR,MS及31P NNMR等手段证明了化合物结构,探讨了溶剂,温度,反应时间,反应物配比及不同底物对反应的影响,对所合成的化合物进行了生物活性测试,结果表明此类五元磷杂环化合物具有一定的生物活性。     

Lawesson试剂在有机合成中的新应用

本文评述了近十年来Lawesson试剂(LR)在有机合成尤其在杂环化合物合成中的新应用。     

有机磷杂环化合物研究（Ⅷ）——Lawesson试剂与含两个氨…

研究Ｌａｗｅｓｓｏｎ试剂与含有两个氨基酸的底物的成环反应，合成了Ｎ－Ｐ－Ｎ型五元，六元磷杂环３ａ－３ｂ，５ａ－５ｂ及８ａ－８ｂ，并讨论了成环机理。初步的生测结果表明，所合成的磷杂环具有一定的除草活性。因此ＬＲ的成环反应合成具有生物活性的磷杂环的新方法。     

3-苯基-4-氯-1,3,4-二氮磷杂环戊-2-硫酮的合成及其除草活性研究

报道了苯基硫脲与脂肪醛(酮)及三氯化磷进行的类Mannich反应,除生成预期产物3-苯基-4-氯-4-氧代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅰ)外,还生成了少量3-苯基-4-氯-4-硫代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅱ).当Ⅰ与Lawesson试剂在甲苯中反应时,可顺利地转化为Ⅱ.生物测定结果表明,Ⅱ具有较好的选择性除草活性.晶体结构测定表明,Ⅱ的五元磷杂环为平面结构.     

连续流动电化学促进的Aza-Wacker环化反应

正饱和N-杂环结构片段广泛存在于各类天然产物和生物活性物质中,且有研究表明提高小分子药物的饱和度有益于改善其临床表现[1].鉴于此,饱和N-杂环化合物的合成受到化学家的广泛关注.在众多饱和N-杂环合成的方法中, Aza-Wacker环化反应显示出独特的优越性,这类反应以胺作为亲核试剂,合成具有烯烃支链的饱和氮杂环分子,产物可方便地进行多样化衍生.经过一段时间的发展,这类反应能够在催化量钯试剂及氧气为氧化剂的条件下完成[2].该反应需要经过氨钯化历程生成产物,该步骤具有可逆性,且受烯烃位阻效应影响,致使一些多取代烯烃的Aza-Wacker环化反应仍具有很大挑战.发展无贵金属试剂、无化学氧化剂条件下的Aza-Wacker环化反应则有利于立足新机理,拓展反应底物的实用范围,同时能有效降低反应成本,发展绿色合成化学[3].     

硅杂六元环化合物的合成

本文综述了环上只含有一个硅原子的硅杂六元环化合物在有机合成方法学方面的进展。介绍了通过α,ω-双金属试剂的关环反应、硅烯参与的[4+2]环加成反应、生成C—Si键的关环反应、生成C—C键的关环反应、硅杂环扩环反应等来合成硅杂六元环化合物,总结了硅杂环己烷、硅杂环己烯以及硅杂环己二烯等不同结构化合物的常见合成方法,为促进硅杂六元环化合物在有机合成化学和材料科学方面的进一步应用提供了基础。     

The synthesis of phosphaisocoumarins by Cu(I)-catalyzed intramolecular cyclization of o-ethynylphenylphosphonic acid monoesters

Cu(I)-catalyzed intramolecular cyclization of o-ethynylphenylphosphonic acid monoethyl esters was examined, and a new class of six-membered phosphorus heterocycles was formed with high regioselectivity and good yields. The present reaction is the first example of intramolecular addition of P-OH to alkynes, which provides a convenient way to synthesize novel phosphorus heterocycles having potential bioactivities.     

Synthesis of phosphaisoquinolin-1-ones by Pd(II)-catalyzed cyclization of o-(1-alkynyl)phenylphosphonamide monoesters

A Pd(II)-catalyzed intramolecular cyclization of o-(1-alkynyl)phenylphosphonamide monoethyl esters was examined, and a new class of six-membered phosphorus heterocycles (phosphaisoquinolin-1-ones) were formed with high regioselectivity and good yields. The present reaction is the first example of intramolecular addition of P-NH to substituted alkynes, which provides a valuable way to synthesize novel phosphorus heterocycles with potential bioactivities.     

Synthesis of biologically active phosphorus heterocycles via cyclization reactions of Lawesson's reagent

2,4‐Bis(4‐methoxyphenyl)‐1,3,2,4‐dithiaphosphetane‐2,4‐disulfide (Lawesson's reagent, LR) reacted with certain bifunctional compounds, such as glycinamides 1, 1‐glyceryl monoesters 4, and 3‐mercapto‐4‐amino‐5‐substituted‐1,2,4‐triazoles 6, to yield five‐membered phosphorus heterocycles 3,5, and 7, respectively. The cycloaddition reaction of LR with 1,3‐butadiene 8 was investigated to form the six‐membered heterocycle 9. The results of preliminary bioassays showed that these heterocycles obtained via cyclization reactions of LR possess significant selective herbicidal activity. The QSAR of 3 was also made. In conclusion, the cyclization reactions of LR with bifunctional substrates and 1,3‐dienes afford novel routes to the syntheses of biologically active phosphorus heterocycles. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 105–111, 1999     

Novel heterocycles. 3. Synthesis of fused 1,3,2-benzodiazaphosphorin ring systems

Novel fused tricyclic phosphorus heterocycles 9 and 11 and the tetracycle 15 were synthesized by cyclization of 1-haloalkyl (or 3-haloalkyl)-2,3-dihydro-1,3,2-benzodiazaphosphorin-4(1H)one 2-oxides with sodium hydride. Some spectral data of the products are also discussed.     

Synthesis of indole-5,6- and carbazole-2,3-dicarboxylic acid functional derivatives

Principal synthetic approaches to the synthesis of indole-5,6- and carbazole-2,3-dicarboxylic acid functional derivatives are considered. The first of them consists in the construction of the indole ring from simpler aromatic compounds containing carboxy groups, cyano groups, or an imide fragment with subsequent reductive cyclization of the compounds formed. The second approach is based on the modification of a pyrrole or an indole fragment by the introduction of different functional groups with subsequent intramolecular cyclization to the corresponding heterocycles.     

Synthesis of 2H-1,2-oxaphosphorin 2-oxides via Ag2CO3-catalyzed cyclization of (Z)-2-alken-4-ynylphosphonic monoesters

[reaction: see text]. Six new 2-ethoxy-2H-1,2-oxaphosphorin 2-oxides were synthesized with high regioselectivity in good yields via Ag(2)CO(3)-catalyzed cyclization of (Z)-2-alken-4-ynylphosphonic monoesters in CH(2)Cl(2) at room temperature. This cyclization of P-OH to substituted alkynes is reported for the first time. The products are a class of phosphorus heterocycles with potential use and are heretofore prepared with difficulty.     

Palladium(0)-catalyzed synthesis of medium-sized heterocycles by using bromoallenes as an allyl dication equivalent

We have developed a highly regio- and stereoselective synthesis of medium-sized heterocycles containing one or two heteroatoms via cyclization of bromoallenes bearing an oxygen, nitrogen, or carbon nucleophilic functionality in the presence of a palladium(0) catalyst and alcohol. In this reaction, bromoallenes act as an allyl dication equivalent, and the intramolecular nucleophilic attack takes place exclusively at the central carbon atom of the allene moiety. Interestingly, bromoallenes having a carbon nucleophile with a five-atom tether afford eight-membered rings with trans-configuration, while those having an oxygen or a nitrogen nucleophile give the corresponding cis-rings selectively. This is the first example that demonstrates the synthesis of medium-sized rings via cyclization of bromoallenes, and this reaction provides a very useful method for a catalytic synthesis of seven- and eight-membered heterocycles without using high dilution conditions.     

Synthetic Routes to Selected Heterocycles Containing Antipyrine Moiety

This review deals with the synthetic potentiality and utility of antipyrine and its derivatives in the synthesis of 4‐substituted antipyrine and other heterocycles containing antipyrine moiety such as thiazole, pyrazolopyridines, pyrazolopyrimidines, and pyrazolotriazines. The reactions that cover the methods of synthesizing the aforementioned heterocycles such as addition, condensation, and cyclization were also reviewed.