Search results for "nucleophilic"

Synthesis of bis(indolylmaleimide) macrocycles

2000

The synthesis of a novel class of macrocyclic bis(indolylmaleimides) is reported. The key step involves the intermolecular connection of 2,2′-bridged indoles with 3,4-dibromo-2,5-dihydro-1H-2,5-pyrroledione (dibromomaleimide) derivatives. The bis(indolylmaleimides) afforded by this method were further processed by intramolecular nucleophilic substitution of the remaining bromo substituents forming flexible N-substituted macrocycles (9a-9j, 10a-10e) and, by connecting both maleimides, semi rigid macrocycles (7a-7xx).

Synthesis, biological evaluation, and: In silico studies of novel chalcone: In pyrazoline-based 1,3,5-triazines as potential anticancer agents

2020

A novel series of triazin-chalcones (7,8)a-g and triazin-N-(3,5-dichlorophenyl)pyrazolines (9,10)a-g were synthesized and evaluated for their anticancer activity against nine different cancer strains. Triazine ketones 5 and 6 were synthesized from the cyanuric chloride 1 by using stepwise nucleophilic substitution of the chlorine atom. These ketones were subsequently subjected to a Claisen-Schmidt condensation reaction with aromatic aldehydes affording chalcones (7,8)a-g. Then, N-(3,5-dichlorophenyl)pyrazolines (9,10)a-g were obtained by cyclocondensation reactions of the respective chalcones (7,8)a-g with 3,5-dichlorophenylhydrazine. Among all the evaluated compounds, chalcones 7d,g and 8g…

Applications of the Conceptual Density Functional Theory Indices to Organic Chemistry Reactivity.

2016

Indexación: Web of Science Theoretical reactivity indices based on the conceptual Density Functional Theory (DFT) have become a powerful tool for the semiquantitative study of organic reactivity. A large number of reactivity indices have been proposed in the literature. Herein, global quantities like the electronic chemical potential μ, the electrophilicity ω and the nucleophilicity N indices, and local condensed indices like the electrophilic and nucleophilic Parr functions, as the most relevant indices for the study of organic reactivity, are discussed. http://www.mdpi.com/1420-3049/21/6/748

Organometallic nucleophiles. Mechanism of halide displacement at saturated carbon by 2-pyridyl and 4-Pyridyl complexes [M(dmtc)(C5H4N-Cn)(L)] (M  Pd…

1992

Abstract A mechanistic study is reported of nucleophilic halide substitution by pyridyl complexes [M(dmtc)C 5 H 4 N- C 2 )(L)] (M  Pd or Pt; L  PMe 3 , PEt 3 or PPh 3 ) and [Pd(dmtc)C 5 H 4 N- C 4 )(L)] (L  PMe 3 or PPh 3 ) on organic halides XCH 2 R (X  Cl or Br; R  CHCH 2 , COMe, Ph, or CN) in various solvents, yielding the pyridylium derivatives [M(dmtc)1-CH 2 R)C 5 H 4 N- C 2 (L)] + and [Pd(dmtc)(1-CH 2 R)(C 5 H 4 N- C 4 (L)] + , respectively. The kinetics obey a second-order rate law: rate  k 2 [XCH 2 R][Complex]. A similar rate law is observed for the analogous reactions involving 4-dimethyl-aminopyridine (4-dmapy) as the nucleophile. The effects of solvent and leaving group, a…

High Yield SNAr on 8-Halogenophenyl-BODIPY with Cyclic and Acyclic Polyamines

2014

Selective nucleophilic aromatic substitutions with several polyamines were performed in very good yields on halogeno-phenyl BODIPY derivatives containing an activating nitro group.

Solution-, solid-phase, and fluorous synthesis of beta,beta-difluorinated cyclic quaternary alpha-amino acid derivatives: a comparative study.

2008

The diastereoselective synthesis of cyclic beta,beta-difluorinated alpha-amino acid derivatives bearing a quaternary stereocenter is described. The process relies on the chemo- and diastereoselective addition of allylic organometallic reagents to fluorinated alpha-imino esters and a subsequent ring-closing metathesis reaction (RCM). Complete selectivity in the nucleophilic addition was achieved with (R)-phenylglycinol methyl ether as a chiral auxiliary. The resulting amino acids were introduced into peptide chains, which could facilitate the preparation of potentially bioactive dipeptide derivatives. In addition, the solution synthesis of these cyclic fluorinated alpha-amino acids was succe…

Iron-Catalyzed C(sp2)–C(sp3) Cross-Coupling of Aryl Chlorobenzoates with Alkyl Grignard Reagents

2020

Aryl benzoates are compounds of high importance in organic synthesis. Herein, we report the iron-catalyzed C(sp2)&ndash

Studies on Adduct Formation of (+)-Anti-Benzo[a]pyrene 7,8-Dihydrodiol 9,10-Epoxide with the oligonucleotides 5′-d(CCTATCGTTATCC) and 5′-d(CCTATm5CGT…

1999

Abstract Adduct formation of (+)-anti-benzo[a]pyrene 7,8-dihydrodiol 9,10-epoxide [BPDE] and 5′-d(CCTATCGTTATCC) or 5′-d(CCTATm5CGTTATCC) (G = binding target) has been studied. The extent of trans-BPDE-N2-dG adduct formation was higher in the oligonucleotide with 5′-d(m5CG) sequence context in both single- and double stranded form compared to the non-methylated analogue. The stimulating effect of m5dC on adduct formation has previously been demonstrated in other experimental systems. The increase in yield could possibly be rationalized in terms of prestacking of the pyrenyl ring with the nucleobases prior to the nucleophilic addition. In the present study, both UV absorption and induced cir…

Back Cover Picture: Coupling of Azomethine Ylides with Nitrilium Derivatives ofcloso-Decaborate Clusters: A Synthetic and Theoretical Study (ChemPlus…

2012

Methyl 4-[5-(4-fluorophenyl)-4-(pyridin-4-yl)-1H-imidazol-2-ylsulfanyl]butanoate

2008

The title compound, C19H18FN3O2S, was synthesized in the course of studies on 2-alkylsufanylimidazoles as p38 mitogen-activated protein kinase inhibitors. The synthesis was achieved by nucleophilic substitution of 4-(4-fluorophenyl)-5-(pyridin-4-yl)-1,3-dihydroimidazole-2-thione with methyl 4-bromobutanoate. The five-membered heterocycle makes dihedral angles of 32.4 (2) and 18.3 (2)° with the fluorophenyl and pyridinyl rings, respectively, indicating a low degree of conjugation between these rings. Intramolecular C—H...N and intermolecular N—H...N hydrogen bonds as well as C—H...π interactions seem to be effective in stabilization of the crystal stru…