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1.
Aurélie Bourderioux 《Tetrahedron》2008,64(49):11012-11019
In the course of a program aimed at designing new antitumor agents, we were interested in the synthesis of new substituted benzo and pyrido carbazoles. The synthesis was performed through an efficient four-step sequence from a 2-trimethylstannylindole derivative and via C-2 (het)arylindoles. The synthetic sequence was developed using two palladium mediated reactions including, at the end of the synthesis, a direct (het)arylannulation, which led to the desired heterocycles. 相似文献
2.
Philip J. Parsons Jonathan Board Davide Faggiani Peter B. Hitchcock Lewis Preece Alexander J. Waters 《Tetrahedron》2010,66(33):6526-6075
A new and highly efficient route for the construction of a model for the synthesis of lactonamycin 1 is reported. The chemistry has been utilised for the synthesis of heterocyclic rings, and new reactions for the synthesis of dienes and alkynes are reported. 相似文献
3.
Reactions of thioamides with nitrogen-rich 1,3-dipoles, diazo compounds and azides, have been known for long time already. However in recent years introduction of catalysts of different types (rhodium-, ruthenium- and copper-containing and Lewis acids) as well as highly electrophilic sulfonyl azides, allowed the development of new methods for the synthesis of heterocycles, enamines and N-sulfonyl amidines. Moreover, a new methodology in organic synthesis, based on generation and subsequent transformations of α-diazocarbonyl compounds was created. Reactions of sulfonyl azides with thioamides undergo readily in mild conditions to produce different sorts of N-sulfonyl amidines and represent a new type of click-type processes. Most of the cited works were published in the current decade. Earlier seminal papers are also reviewed when they constitute the background for new synthetic methods which were developed further. 相似文献
4.
Emtenäs H Ahlin K Pinkner JS Hultgren SJ Almqvist F 《Journal of combinatorial chemistry》2002,4(6):630-639
A new method for the solid-phase synthesis of enantiomerically enriched highly substituted ring-fused 2-pyridinones 13 has been developed. The synthesis mediates introduction of substituents at two positions in the 2-pyridinone ring in a diverse manner and is suitable for parallel synthesis. (19)F NMR spectroscopy was used as a tool to monitor each of the five steps in the reaction sequence. The optimized conditions thus obtained were then used to prepare a library of 20 2-pyridinones with high yields. The library members were chosen from a statistical multivariate design to ensure diversity and reliable data for structure-activity relationships. Screening of the library against the bacterial periplasmic chaperone PapD was performed using surface plasmon resonance. Three new 2-pyridinones with a higher affinity for the chaperone PapD than the previous best 13[10,1] were found, and important structural features could be deduced. 相似文献
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For the first time fluoropyrimidines were successfully lithiated. The resulting lithio derivatives were reacted with various electrophiles for the synthesis of new pyrimidines. The synthesis of an azacarboline derivative is reported. 相似文献
8.
Vincent Lapinte Laurent Fontaine Vronique Montembault Irne Campistron Danile Reyx 《Journal of molecular catalysis. A, Chemical》2002,190(1-2):117-129
ROMP and retro-acyclic diene metathesis (ADMET) were used for the synthesis of new functional polymers and functional oligomers, respectively. Purely exo and enantiomerically pure norbornene and 7-oxanorbornene derivatives were prepared using stereospecific synthesis, effective fractionation and high yield condensation reactions. Successful ROMPs of those monomers were performed using either the new carbenic Schrock’s or Grubb’s catalysts or in some cases a classical bicomponent catalyst. New functional polymers such as optically active poly(norbornene-2-carboxylic acid), reactive poly(norbornene-2-azlactone), and side-chain liquid crystal polyoxanorbornenes were fully characterized. On the other hand, successful depolymerizations of 1,4-polyisoprene and of epoxidized 1,4-polybutadiene via cross-metathesis with 4-octene were performed using a stabilized bicomponent catalyst and the Grubb’s catalyst, respectively. Conditions for the controlled synthesis of epoxidized oligobutadienes and of epoxydienic monomers via retro-ADMET were clearly defined. 相似文献
9.
Bolian Xu Ruiqin Yang Fanzhi Meng Prasert Reubroycharoen Tharapong Vitidsant Yi Zhang Yoshiharu Yoneyama Noritatsu Tsubaki 《Catalysis Surveys from Asia》2009,13(3):147-163
Low temperature methanol synthesis is a promising technique for the practical methanol industry. New developments of a new
kind of low temperature methanol synthesis were reviewed, including the effects of feed gas, reaction solvent, supercritical
media and catalyst modification. The reaction mechanism and kinetics were also summarized primarily. Carbon dioxide played
an important role in this new kind of low temperature methanol synthesis. It reacted with hydrogen adsorbed on catalyst surface
to form HCOOM, an important reaction intermediate. Alcohol solvent in the low temperature methanol synthesis performed not
only a media, but also a homogeneous catalyst. The reaction of the adsorbed formate species with alcohol on Cu/ZnO catalyst
surface proceeded according to the Rideal mechanism rather than Langmuir–Hinshelwood mechanism to form alkyl formate. The
formation of alkyl formate from alcohol solvent and hydrogenation of such an alkyl formate were the key steps in low temperature
methanol synthesis reaction. These results provided new insights into low temperature methanol synthesis. 相似文献
10.
Sadikov N Nasibov S Oğretir C Berber H Hüseyinli A 《Molecules (Basel, Switzerland)》2004,9(11):922-938
The alkylation of beta-dicarbonyl compounds in a K2CO3/DMSO system was found to afford O- and C-alkylated derivatives, depending on the type of the beta-dicarbonyl compound involved. The alkyl derivatives obtained were used in the synthesis of some new spiro barbituric acid derivatives. Quantum chemical calculations were carried out to elucidate the reaction mechanisms for some typical synthesis. 相似文献
11.
The mechanism and regulation of cellulose synthesis in primary walls: lessons from cellulose-deficient Arabidopsis mutants 总被引:1,自引:0,他引:1
Cellulose-deficient Arabidopsis mutants were identified using FT-IR microspectroscopy. The study of these mutants not only led to the identification of actors in cellulose synthesis, but also provided insights in the organization of the hexameric terminal complex from CESA mutants and identified unsuspected accessory proteins with so far unknown roles in the synthesis and/or assembly of cellulose microfibrils. Finally, mutant analysis established a role for protein glycosylation in cellulose synthesis and provided new perspectives on the developmental regulation of cell wall synthesis and the role that cellulose synthesis plays in the control of cell elongation. 相似文献
12.
Dr. Maria Grazia Martina Dr. Lisa Giannessi Prof. Dr. Marco Radi 《European journal of organic chemistry》2023,26(2):e202201288
It is widely accepted that purines and pyrimidines, the building blocks that gave origin to life on our planet, were created through multicomponent reactions (MCRs) on early abiotic Earth. These heterocyclic scaffolds gradually evolved into a wide range of biologically relevant molecules regulating many different physiological processes and thus becoming widely exploited as templates for the development of new drugs. Accordingly, over the years, the synthetic community has dedicated many efforts in the attempt to hypothesize and replicate the original abiotic synthesis of purines and pyrimidines, thus developing a number of multicomponent synthesis to access these scaffolds. The following evolution of synthetic chemistry towards green approaches for the production of new molecules and the recent interest in pharmaceutical sustainability underlines the importance of multicomponent synthesis of new heterocycles. This review article provides an overview of the most important multicomponent approaches for the synthesis of purine and pyrimidine derivatives for potential pharmacological applications. 相似文献
13.
Masaki Okamoto 《Research on Chemical Intermediates》2006,32(3):317-330
In the direct synthesis of silicon compounds by reactions of elemental silicon with methyl chloride, methanol and hydrogen
chloride, silylene formed on surface of silicon grains during the reaction is an intermediate. The reaction of surface silylene
with a variety of unsaturated hydrocarbons provides new direct synthesis of organosilanes. In the direct synthesis of methylchlorogermanes
from elemental germanium, surface germylene is not an intermediate, while tetrachlorogermane is synthesized by the direct
reaction of germanium with hydrogen chloride via dichlorogermylene intermediate. Various unsaturated hydrocarbons or organic chlorides added to the system of tetrachlorogermane
synthesis give new methods for the synthesis of organogermanes. 相似文献
14.
Masaki Okamoto 《Research on Chemical Intermediates》2006,32(3-4):317-330
In the direct synthesis of silicon compounds by reactions of elemental silicon with methyl chloride, methanol and hydrogen chloride, silylene formed on surface of silicon grains during the reaction is an intermediate. The reaction of surface silylene with a variety of unsaturated hydrocarbons provides new direct synthesis of organosilanes. In the direct synthesis of methylchlorogermanes from elemental germanium, surface germylene is not an intermediate, while tetrachlorogermane is synthesized by the direct reaction of germanium with hydrogen chloride via dichlorogermylene intermediate. Various unsaturated hydrocarbons or organic chlorides added to the system of tetrachlorogermane synthesis give new methods for the synthesis of organogermanes. 相似文献
15.
Arata Yajima 《Tetrahedron》2005,61(38):9164-9172
A versatile methodology for the synthesis of various terpenoids via B-alkyl Suzuki-Miyaura coupling as a key step is established. Synthesis of cordiaquinone J and K, new antifungal and larvicidal meroterpenoids, was achieved by using this methodology. The absolute configurations of cordiaquinone J and K were confirmed by the synthesis. 相似文献
16.
Ana Bellomo Ana Bertucci Hélio Stefani Álvaro Vázquez David Gonzalez 《Tetrahedron: Asymmetry》2009,20(23):2673-2676
The first synthesis of two selenyldeoxycyclitols (4-bromo-2-phenylselenyl conduritol F and 6-phenylselenylconduritol F) is reported via a chemoenzymatic enantioselective route. The key step of the synthesis is the selenolysis of a vinyl epoxide. The new compounds were evaluated for their capacity to inhibit the growth of different microorganisms using a modification of the agar diffusion technique with thin layer chromatography plates as support. 相似文献
17.
Iptycene-derived pyridazines and phthalazines 总被引:1,自引:0,他引:1
The synthesis of new heterocyclic oligo(phenylene) analogues based on soluble, nonaggregating 1,2-diazines is reported. Improved palladium-catalyzed reductive coupling methods were developed to allow for the preparation of large quantities of iptycene-derived bipyridazines and biphthalazines, and the controlled synthesis of well-defined oligomers up to sexipyridazine. Crystallographic, spectroscopic, and computational evidence indicate that in these analogues, hindrance at the ortho position is relaxed relative to poly(phenylenes). The resulting building blocks are promising for incorporation in conjugated electronics materials, and as new iptycene-derived ligands for transition metals. 相似文献
18.
An efficient synthesis of spiro-fused macrolactams by a multicomponent macrocyclization reaction (MCMR) is reported. The use of highly reactive, transient intermediates in this MCMR permits short reaction times, even at high dilution. The methods employed for this MCMR were first developed as a four-component strategy for the synthesis of β-ketoamide isoxazolines and a new macrocyclization reaction is reported. 相似文献
19.
Sapurina I. Yu. Frolov V. I. Shabsel's B. M. Stejskal J. 《Russian Journal of Applied Chemistry》2003,76(5):835-839
Production of a new conducting composite material based on polyaniline and wood by simple one-stage synthesis from aniline and wood sawdust is described. The material characteristics were studied in relation to the synthesis conditions and composition. 相似文献
20.
A. S. Seleznev L. A. Petrov O. N. Chupakhin V. I. Kononenko I. A. Chupova A. V. Ryabina 《Russian Journal of Applied Chemistry》2009,82(5):820-825
To improve cobalt-containing catalytic systems for synthesis of hydrocarbons from carbon monoxide and hydrogen (Fischer-Tropsch synthesis), supports based on ultradispersed alloys of aluminum with rare and rare-earth metals (G, Ce, Sm) were obtained and studied. The catalytic activity parameters of the new catalysts were determined. 相似文献