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1.
Benzo[c]phenanthridine alkaloid, 7-hydroxynitidine, was synthesized from readily available 2-benzyloxy-6-bromo-3,4-dimethoxybenzaldehyde 5 and napthylamine 6 using reductive amination followed by radical cyclization in eight steps. This method is highly efficient and better way to synthesize fully aromatized benzo[c]phenanthridine compounds. 相似文献
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ZhiQin Zou ZeJun Deng XinHong Yu ManMan Zhang SiHan Zhao Ting Luo Xin Yin Hui Xu Wei Wang 《中国科学:化学(英文版)》2012,55(1):43-49
An unprecedented acetic acid-catalyzed efficient access to N-alkylpyrroles from reaction of 4-hydroxy-L-proline with a variety of aldehydes has been achieved in good to excellent yields under mild reaction conditions. 相似文献
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De Xin FENG Ru Yu CHEN You HUANG 《中国化学快报》2006,17(9):1145-1148
Regioselective cyclization of 1-acylthiosemicarbazides has been shown to be an excellent method for the synthesis of triazoles, thiadiazoles and oxadiazoles, with a variety of potential biological activities1-6 and utilities as pharmacological properties7… 相似文献
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A new approach to the synthesis of 5-substituted 2-methyl-1,3,4-oxadiazoles was developed. 相似文献
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3-正丙基-4-氨基-5-酰胺基-1-甲基吡唑的合成 总被引:2,自引:0,他引:2
以2-戊酮为起始原料,经Claisen缩合、环化、甲基化、皂化、硝化、酰胺化和还原反应,制得目标化合物。总收率比文献报道值提高一倍,达46.8%。 相似文献
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Nicolas PhilippeFrançois Denivet Jean-Luc VasseJana Sopkova-de Olivera Santos Vincent Levacher Georges Dupas 《Tetrahedron》2003,59(40):8049-8056
The present report describes a stereoselective synthesis of 1,4-dihydro-4-phenyl isoquinolinones 5 based on a stereoselective Friedel-Crafts type cyclization. Cyclization precursors 1 were prepared in two steps, from the readily available (S)-mandelic acid, in 60-80% overall yield. The stereoselective electrophilic cyclization was accomplished in 20-86% yield and with 20-97% ee. In the course of this work, the presence of the amide carbonyl was found to be particularly important to guarantee a stereospecific process during the electrophilic aromatic substitution. 相似文献
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Vicente Gómez-Parra Félix Sánchez Tomás Torres 《Monatshefte für Chemie / Chemical Monthly》1985,116(5):639-644
A new procedure for preparing 1-alkyl-1,3-dihydro-2H-benzimidazol-2-ones fromo-nitroanilines by successive ethoxycarbonylation, catalytic hydrogenation and thermal cyclization under neutral conditions is described.
Eine neue Synthese von 1-Alkyl-1,3-dihydro-2H-benzimidazol-2-onen
Zusammenfassung Eine neue Methode zur Darstellung von 1-Alkyl-1,3-dihydro-2H-benzimidazol-2-onen auso-Nitroanilinen durch Ethoxycarbonylierung, katalytische Hydrierung und thermische Cyclisierung wird beschrieben.相似文献
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The scope and limitations of the reaction between imidates and α,α-disubstituted α-aminoacetonitriles to give 5-amino-4H-imidazoles are studied. The reactivity of compounds 1a-b has been explored. 相似文献
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A new approach to the synthesis of benzomorphan derivatives is exemplified by the obtention of 3,6-dimethyl-benzomorphan from the readily available 1-methyl-2,3-benzobicyclo-[3,2,l]octane-4,6-dione. 相似文献
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Bourahla K Paquin L Lozach O Meijer L Carreaux F Bazureau JP 《Molecules (Basel, Switzerland)》2011,16(9):7377-7390
A practical protocol for the preparation of (5Z)-2-alkylthio-5-arylmethylene-1-methyl-1,5-dihydro-4H-imidazol-4-one derivatives is reported. The new compounds were obtained in good yield and stereoselectivity in two steps, namely a solvent-free Knoevenagel condensation under microwave irradiation, followed by an S-alkylation reaction with various halogenoalkanes. 相似文献
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A new synthetic method for phosphatidylethanolamine head group was developed via ring-opening of cyclic dioxaphospholane 2 with sodium azide and subsequent hydrogenation.The advantage of this strategy included short reaction steps,readily available materials and good yields. 相似文献
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3-(1-Alkoxyvinyl)-1-aminoallenes 6 were generated by conjugate addition of acyclic and cyclic (1-alkoxyvinyl)cuprates with the semicyclic propyne iminium salt 4. They isomerized smoothly into spiroannellated cyclopentadienes 7 through a 1,5-cyclization that in some cases occurred already at ≤20°C. (1-Methoxyallenyl)cuprates reacted with salt 4 in a 2:1 ratio to give the 5,5-dimethoxy-4-methylenepentalene-1-spiro-2′-dihydroindole derivative 10. The thermal isomerization of morpholinoallene 12 into cyclopentadiene 13 indicates that the novel 1,5-cyclization can be extended to other 3-(1-alkoxyvinyl)-1-aminoallenes as well. 相似文献
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Mauro F.A. Adamo Simone Bruschi Surisetti Suresh Linda Piras 《Tetrahedron letters》2008,49(52):7406-7409
Herein we describe the preparation of a novel class of isoxazolyl aziridines. The products were obtained exclusively as cis diastereoisomers. 相似文献
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Egle M. Beccalli 《Tetrahedron letters》2004,45(17):3447-3449
A new synthesis of [1]benzopyrano[4,3-b]pyridin-5-ones 4 was developed starting from 3-formyl-coumarin N-functionalized amidines 3. The reaction is based likely on the intramolecular cyclocondensation of the C-α amidinic carbanion in basic medium on the formyl group. 相似文献
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Daniella TakácsOrsolya Egyed László DrahosZsuzsanna Riedl György Hajós 《Tetrahedron letters》2012,53(42):5585-5588
Elaboration of a Buchwald-Hartwig protocol for the introduction of amino functions to position 2 of the phenothiazine ring system has opened a new access to various N-alkyl and N-dienyl phenothiazines bearing secondary amines, tertiary amines, and amide moieties. Hydrolysis of the amido derivatives gave unsubstituted phenothiazine-2-amines. This protocol provides an easy access to phenothiazine-2-amines starting from the commercially available starting compounds. 相似文献
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An entry to 7-amino- and to 2-ethoxycarbonyl-5-dethia-5-oxa-cephams from 1,3-alkylidene-l-erythritol
The alkoxyallene derived from 1,3-benzylidene-l-erythritol when treated with chlorosulfonyl isocyanate provided diastereomeric β-lactams with moderate stereoselectivity. After the intramolecular alkylation of the nitrogen atom, these afforded compounds having oxacepham skeletons. The exo-isopropylidene group enabled the introduction of a variety of substituents to the C-7 carbon atom of the cepham, whereas removal of the benzylidene protection followed by the oxidation of 3-OH to the ketone allowed carboxylation of the C-2 carbon atom. 相似文献
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