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取代的吲哚类天然产物是自然界中普遍存在的一类杂环化合物,由于其具有广泛的生理活性,以及相当一部分作为重要的临床使用药物,100多年以来,吲哚的合成及官能团化一直是有机合成化学家关注的一个重要领域.在众多吲哚类生物碱中,含有3,4-桥环吲哚骨架的天然产物占据了相当一部分,由于其独特的结构和良好的生物活性,这些分子引起了有机合成化学家的广泛兴趣.重点概述了构建3,4-桥环骨架的主要合成方法和策略,并对一些方法在天然产物全合成中的应用作简要介绍. 相似文献
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以3,5-二取代异噁唑-4-甲酰肼为基本原料制备关键中间体1-(3-对甲氧基苯基-5-甲基异噁唑-4-基)-4-芳基氨基硫脲(3a~3c);3在不同条件下经关环反应制得含有3,5-二取代异噁唑的2-芳氨基噻二唑(4a~4c),2-芳氨基噁二唑(5a~5c)和3-[3′-(4"-甲氧基苯基)-5′-甲基-异噁唑4′-基)-4-芳基-1,2,4-三唑-5-硫酮(6a~6c);6与碘甲(乙)烷反应合成了4-芳基-5-[3′-(4″-甲氧基苯基)-5′-甲基异噁唑-4′-基]-3-甲(乙)硫基-1,2,4-三唑(7a~8c),其结构经1H NMR,IR,MS和元素分析表征,其中4,5,7和8未见文献报道. 相似文献
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利用生物活性亚结构拼接原理,将吡啶环、噻唑环引入到1,3,4-噁二唑母体结构中,设计并合成了一系列新型含吡啶(噻唑)的1,3,4-噁二唑衍生物.通过IR,1H NMR,EI-MS及元素分析等方法对所合成的化合物进行了结构表征.代表化合物2-(6-氯吡啶-3-甲硫基)-5-(吡啶-4-基)-1,3,4-噁二唑(I)经单晶X衍射证实了结构.初步测定了所合成化合物的杀菌活性,并比较了在1,3,4-噁二唑母体结构中引入噻唑杂环和引入吡啶杂环后其杀菌活性的差异.结果表明:目标化合物对测试的5种菌均具有一定的杀菌活性,对水稻纹枯病的抑制效果普遍优于对其它菌种的抑制效果;在1,3,4-噁二唑母体结构中引入噻唑杂环比引入吡啶杂环对其杀菌活性更有利. 相似文献
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以3,5-二取代异噁唑-4-甲酰肼为基本原料制备关键中间体1-(3-对甲氧基苯基-5-甲基异噁唑-4-基)-4-芳基氨基硫脲(3a~3c);3在不同条件下经关环反应制得含有3,5-二取代异噁唑的2-芳氨基噻二唑(4a~4c),2-芳氨基噁二唑(5a~5c)和3-[3’-(4″-甲氧基苯基)-5’-甲基-异噁唑-4’-基)-4-芳基-1,2,4-三唑-5-硫酮(6a~6c);6与碘甲(乙)烷反应合成了4-芳基-5-[3’-(4″-甲氧基苯基)-5’-甲基异噁唑-4’-基]-3-甲(乙)硫基-1,2,4-三唑(7a~8c),其结构经1H NMR,IR,MS和元素分析表征,其中4,5,7和8未见文献报道。 相似文献
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基于具有潜在杀线虫活性的托烷衍生物结构,通过1,3-偶极环加成反应,设计合成了19个未见报道的8-氮杂双环[3.2.1]辛烷-3-异噁唑肟类衍生物,通过~1H NMR,~(13)C NMR和高分辨质谱对目标化合物的结构进行表征.初步的生物活性测试表明:在浓度25 mg/L下,目标化合物对南方根结线虫表现出良好的抑制活性,活性最好的化合物8-甲基-8-氮杂双环[3.2.1]辛烷-3-酮-O-((3-(4-硝基苯基)-4,5-二氢异噁唑-5-基)甲基)肟(9e)在1 mg/L浓度下对根结线虫的抑制率达55.6%. 相似文献
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《有机化学》2015,(10)
氧化吲哚螺环类结构因具广泛的生物活性,已逐渐成为一类重要的类药性骨架.因此,开发简单高效的合成方法构建复杂的氧化吲哚螺环类化合物库已经成为化学工作者广泛关注的研究方向之一.由于现代有机化学倍受中间产物分离提纯及官能团保护、脱保护策略等的困扰,而串联反应的出现为克服以上诸多难题提供了机遇,且在合成具有光学活性的天然产物和复杂分子中显示了它潜在的优势.近年来,通过有机串联反应策略不对称合成氧化吲哚螺环类化合物备受关注,大量的研究工作被报道.分别从C(3)位不饱和氧化吲哚衍生物、饱和氧化吲哚衍生物、C(3)位无取代氧化吲哚衍生物以及非氧化吲哚衍生物四大类起始原料出发,简单综述了近5年来氧化吲哚螺环化合物的合成方法进展,并对各类反应对底物要求、反应条件、反应选择性、产率以及机理的研究进行了讨论和总结. 相似文献
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Sergio Mantegani Gabriella Traquandi Mario Varasi 《Journal of heterocyclic chemistry》2001,38(3):759-763
As a part of a search for novel biological active ergoline derivatives, the indole ring present in the ergoline skeleton (indole[4,3‐f,g]quinoline) was converted into different heterocyclic ring systems such as quinazoline 2 , benzofurane 3 and benzoxazole 4 . Due to the paramount importance of chirality to attain biological activity, natural dihydrolysergic acid 1 was chosen as starting material and a synthetic pathway conservative in term of chirality was followed. 相似文献
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The total synthesis of several members of the vinca and tacaman classes of indole alkaloids has been accomplished. The central step in the synthesis consists of an intramolecular [3+2]-cycloaddition reaction of an alpha-diazo indoloamide which delivers the pentacyclic skeleton of the natural product in excellent yield. The acid lability of the oxabicyclic structure was exploited to establish the trans-D/E ring fusion of (+/-)-3H-epivincamine (3). Finally, a base induced keto-amide ring contraction was utilized to generate the E-ring of the natural product. A variation of the cascade sequence of reactions used to synthesize (+/-)-3H-epivincamine was also employed for the synthesis of the tacaman alkaloids (+/-)-tacamonine and (+/-)-apotacamine. 相似文献
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B. M. Krasovitskii L. A. Kutulya A. E. Shevchenko L. Sh. Afanasiadi N. P. Egorova A. L. Shvorina 《Chemistry of Heterocyclic Compounds》1977,13(5):532-537
A number of trans-stilbene derivatives containing 2-pyrazolinyl and 1,3-oxazolyl groupings were synthesized by PO olefination from 1-(4-formylphenyl)-3-aryl-5-phenyl-2-pyrazolines and 2-(4-bromomethylphenyl)-5-phenyl-1,3-oxazole. The products fluoresce intensely in the green or yellow-green region (quantum yields 0.4–0.57). The intense long-wave absorption band of the investigated compounds is due to an electron transition that is localized primarily in the stilbene fragment of their molecules that includes, as a substituent, the amine nitrogen atom of the pyrazoline ring; the less intense shortwave band corresponds to localization of the electronic excitation in the hydrazone grouping.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 656–661, May, 1977. 相似文献
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Benzothiophene, benzofuran, indole, and indene derivatives are privileged heterocyclic motifs. These are present in a wide range of bioactive natural products and pharmaceutical drugs and are the subject of materials science research. However, the construction of benzothiophene, benzofuran, indole, and indene frameworks have been long‐standing challenges to organic chemists. In this review, we classify the derivatives of four structures synthesized from 2‐benzylidene‐1‐benzofuran‐3‐one and their analogues in terms of their ring size (from three‐ to ten‐membered) and type (fused or spiro), as well as summarizing the developments of this field. Finally, we discuss the ring opening and 1,4‐addition reactions. 相似文献
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4-(5-Aryl-2-oxazolyl)-substituted phthalic anhydrides were synthesized from 4-chloroformylphthalic anhydride and various -aminomethyl aryl ketones. The spectral-luminescence properties of solutions of the products in toluene and 5% NaOH solution were investigated. It is shown that the introduction of substituents with different electronic natures in the 5-phenyl ring of 4-(5-phenyl-2-oxazolyl) phthalic anhydride has a significant effect on the spectral-luminescence characteristics of the synthesized compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 35–37, January, 1979. 相似文献
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[reaction: see text] Nominine (1) and aspernomine (2) are two biologically important indole diterpenoids that arise from a common digeranylindole precursor. The skeletal relationship of these two natural products was not heretofore understood. We have observed a novel rearrangement of 2-(2-bromophenyl)-3-(3-butenyl)-3H-indol-3-ol (5) to 7, which contains the uncommon 1,4,5,6-tetrahydro-2,6-methano-1-benzazocin-3(2H)-one ring system, under acidic conditions. This rearrangement suggests that aspernomine (2) may arise biosynthetically from nominine (1). 相似文献
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A new method for the synthesis of the octahydropyrrolo[3,2,1-ij]quinoline ring system that possesses the characteristic skeleton of the aspidosperma family of alkaloids has been developed. The method utilizes an intramolecular Diels-Alder reaction of an amido-substituted furan across a tethered indole pi-bond. To apply this strategy to the synthesis of the indole alkaloid spegazzinidine, it was necessary to address the problem of assembling the final D-ring of the pentacyclic skeleton. Radical cyclization of a model N-allyl-7-bromo-3a-methylhexahydroindolinone system was found to preferentially lead to the 6-endo-trig cyclization product, with the best yield being obtained under high dilution conditions. The six-membered cyclized product is generated through two reaction pathways: (a) 6-endo-trig ring closure and (b) rearrangement of an intermediate methylene-cyclopentyl radical obtained by 5-exo-trig cyclization. A number of related 7-bromo-substituted hexahydroindolinones containing tethered olefinic groups were prepared and found to undergo efficient cyclization under both radical and palladium-mediated reaction conditions. Vinyl radical cyclization with several N-butenyl-substituted systems afforded a mixture of 6-exo and 7-endo cyclization products. A protocol to introduce an ethyl substituent into the C20-position of the aspidospermidine skeleton was also developed. 相似文献
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E. V. Rudyakova V. A. Savosik I. T. Evstaf’eva E. V. Kondrashov G. G. Levkovskaya 《Russian Journal of Organic Chemistry》2009,45(5):705-711
Synthesized 1-benzyl-3-chloroalkyl-5-chloropyrazoles reacted with indole and pyrrole in DMSO in the presence of alkali to give 3-(heter-1-yl)alkyl-substituted 1-benzyl-5-chloropyrazoles. 1-[(1-Benzyl-5-chloropyrazol-3-yl)methyl]indole reacted regiospecifically with chloroal trifluoromethylsulfonyl- and 4-chlorophenylsulfonylimines providing the products of C-amidotrichloroethylation into the position 3 of the indole ring. {1-[(1-Benzyl-5-chloropyrazol-3-yl)methyl]indol-3-yl}sulfanylacetic acid was obtained by the reaction of 1-[(1-benzyl-5-chloropyrazol-3-yl)methyl]-indole with iodine, thiourea, and chloroacetic acid. 相似文献
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Bonneau AL Robert N Hoarau C Baudoin O Marsais F 《Organic & biomolecular chemistry》2007,5(1):175-183
The synthesis of three novel racemic phenylpyridine-carbamate analogues of rhazinilam and their biological evaluation as inhibitors of microtubule assembly and disassembly by interaction with tubulin are described. The sterically hindered ortho-disubstituted biaryl unit as the challenging key structural element is first obtained by a sequential regiocontrolled nucleophilic addition of a lithium ortho-lithiohomobenzylic alkoxide species to 3-bromo-5-oxazolyl pyridine as the electrophile and a subsequent oxidation step. The incorporation of the amino group by replacement of the bromide has been achieved using a Buchwald-Hartwig amination coupling. Ultimate deprotection steps furnished free-amino and free-hydroxyl appendages which were connected by phosgenation to furnish the nine-membered median carbamate ring. 相似文献
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4-(2-Methyl-5-oxazolyl)naphthalic anhydridewas synthesized by heating -aminomethyl 5-acenaphthyl ketone hydrochloride with acetic anhydride and subsequent oxidation of the resulting 2-methy1-5-(5-acenaphthyl)oxazole. 4-(2-Methyl-5-oxazolyl)-naphthalic acid phenylimide and 4(3)-(2-methyl-5-oxazolyl)-7-oxo-7H-benzimidazo-[1,2-b]benzo[de]isoquinoline were obtained by condensation of 4-(2-methy1-5-oxazo-lyl)naphthalic anhydride with aniline and o-phenylenediamine. The coincidence of the directions of polarization of the C=N bond of the oxazole ring and the electronic shifts in the system of the anhydride and phenylimide molecules leads to an increase in the quantum luminescence yield.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1613–1615, December, 1977. 相似文献