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Pyrrolidine dithiocarbamate down-regulates vascular matrix metalloproteinases and ameliorates vascular dysfunction and remodelling in renovascular hypertension

CAU, S. B. A.; GUIMARAES, D. A.; RIZZI, E.; CERON, C. S.; SOUZA, L. L.; TIRAPELLI, C. R.; GERLACH, R. F.; TANUS-SANTOS, J. E.
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
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37.01%
BACKGROUND AND PURPOSE Mounting evidence implicates matrix metalloproteinase (MMP) in the vascular dysfunction and remodelling associated with hypertension. We tested the hypothesis that treatment with pyrrolidine dithiocarbamate (PDTC), which interferes with NF-kappa B-induced MMPs gene transcription, could exert antihypertensive effects, prevent MMP-2 and MMP-9 up-regulation, and protect against the functional alterations and vascular remodelling of two-kidney, one clip (2K1C) hypertension. EXPERIMENTAL APPROACH Sham-operated or hypertensive rats were treated with vehicle or PDTC (100 mg.Kg(-1).day(-1)) by gavage for 8 weeks. Systolic blood pressure (SBP) was monitored weekly. Aortic rings were isolated to assess endothelium-dependent relaxations. Quantitative morphometry of structural alterations of the aortic wall was carried out in haematoxylin/eosin sections. Formation of vascular reactive oxygen species (ROS), and inducible (i) NOS and phosphorylated-p65 NF-kappa B subunit expression were measured in the aortas. MMP-2 and MMP-9 aortic levels and gelatinolytic activity were determined by gelatin and in situ zymography and by immunofluorescence. KEY RESULTS Treatment with PDTC attenuated the increases in SBP and prevented the endothelial dysfunction associated with 2K1C hypertension. Moreover...

Aplicação de metodologias do CADD (Computer-Aided Drug Design) a um conjunto de pirrolidina carboxamidas: mapeamento do farmacóforo e planejamento de novos protótipos tuberculostáticos potenciais; Computer-Aided drug design methodologies applied to a set of pyrrolidine carboxamides: pharmacophore mapping and planning of new prototypes potential tuberculostatic

Silva, Bárbara Athayde Vaz Galvão da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/03/2012 PT
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A situação da tuberculose (TB) foi alterada de forma significativa pela síndrome de imunodeficiência adquirida (SIDA ou AIDS) e pelo aparecimento de novas cepas do Mycobacterium tuberculosis resistentes ao tratamento quimioterápico, que justificariam a pesquisa de novos agentes antimicobacterianos. Alvos interessantes têm emergido para o planejamento racional de novos fármacos contra a TB, particularmente, considerando processos metabólicos específicos que ocorrem durante a biossíntese da parede celular micobacteriana e que envolvem a síntese de ácidos graxos (FAS-II, fatty acid synthase). O sistema FAS-II constitui diferença bioquímica importante entre mamíferos e micobatérias. A enzima enoil-acp (acyl carrier protein, proteína acil-carregadora) redutase (ENR) é alvo determinante no sistema FAS-II, responsável pela etapa de alongamento dos ácidos micólicos, que são os principais componentes da parede celular do M. tuberculosis. O presente projeto tem como objetivo a aplicação de metodologias do planejamento de fármacos auxiliado por computador, CADD (Computer-Aided Drug Design), em um conjunto de derivados pirrolidina carboxamidas descritos como inibidores potenciais da ENR do M. tuberculosis (InhA) com intuito de mapear o farmacóforo...

Correlation between Polyamines and Pyrrolidine Alkaloids in Developing Tobacco Callus 1

Tiburcio, Antonio Fernández; Kaur-Sawhney, Ravindar; Ingersoll, Royal B.; Galston, Arthur W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1985 EN
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Since the diamine putrescine can be metabolized into the pyrrolidine ring of tobacco alkaloids as well as into the higher polyamines, we have investigated the quantitative relationship between putrescine and these metabolites in tobacco callus cultured in vitro. We measured levels of free and conjugated putrescine and spermidine, and pyrrolidine alkaloids, as well as activities of the putrescine-biosynthetic enzymes arginine and ornithine decarboxylase. In callus grown on high (11.5 micromolar) α-naphthalene acetic acid, suboptimal for alkaloid biosynthesis, putrescine and spermidine conjugates were the main putrescine derivatives, while in callus grown on low (1.5 micromolar) α-naphthalene acetic acid, optimal for alkaloid formation, nornicotine and nicotine were the main putrescine derivatives. During callus development, a significant negative correlation was found between levels of perchloric acid-soluble putrescine conjugates and pyrrolidine alkaloids. The results suggest that bound putrescine can act as a pool for pyrrolidine alkaloid formation in systems where alkaloid biosynthesis is active. In addition, changes in arginine decarboxylase activity corresponding to increased alkaloid levels suggest a role for this enzyme in the overall biosynthesis of pyrrolidine alkaloids.

INHIBITION OF TOXOPLASMA GONDII GROWTH BY PYRROLIDINE DITHIOCARBAMATE IS CELL CYCLE SPECIFIC AND LEADS TO POPULATION SYNCHRONIZATION

Conde de Felipe, Magnolia M.; Lehmann, Margaret M.; Jerome, Maria E.; White, Michael W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Successful completion of the Toxoplasma cell cycle requires the coordination of a series of complex and ordered processes that results in the formation of two daughters by internal budding. Although we now understand the order and timing of intracellular events associated with the parasite cell cycle, the molecular details of the checkpoints that regulate each step in T. gondii division is still uncertain. In other eukaryotic cells, the use of cytostatic inhibitors that are able to arrest replication at natural checkpoints have been exploited to induce synchronization of population growth. Herein, we describe a novel method to synchronize T. gondii tachyzoites based on the reversible growth inhibition by the drug, pyrrolidine dithiocarbamate. This method is an improvement over other strategies developed for this parasite as no prior genetic manipulation of the parasite was required. RH tachyzoites blocked by pyrrolidine dithiocarbamate exhibited a near uniform haploid DNA content and single centrosome indicating that this compound arrests parasites in the G1 phase of the tachyzoite cell cycle with a minor block in late cytokinesis. Thus, these studies support the existence of a natural checkpoint that regulates passage through the G1 period of the cell cycle. Populations released from pyrrolidine dithiocarbamate inhibition completed progression through G1 and entered S phase ~2 hours post-drug release. The transit of drug-synchronized populations through S phase and mitosis followed a similar timeframe to previous studies of the tachyzoite cell cycle. Tachyzoites treated with pyrrolidine dithiocarbamate were fully viable and completed two identical division cycles post-drug release demonstrating that this is a robust method for synchronizing population growth in Toxoplasma.

4′-(4-Methoxy­phen­yl)-1,1′,1′′-trimethyl­dispiro­[indoline-3,2′-pyrrolidine-3′,3′′-pyrrolidine]-2,2′′,5′′-trione

Nirmala, S.; Karthikeyan, K.; Kamala, E. Theboral Sugi; Sudha, L.; Perumal, P. T.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 20/06/2009 EN
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In the title compound, C24H25N3O4, the pyrrolidine ring adopts an envelope conformation while the pyrrolidine-2′′,5′′-dione ring adopts a twist conformation. The indoline unit is planar [maximum deviation of −0.050 (9) Å] and forms a dihedral angle of 40.36 (4)° with the methoxy­phenyl ring. Intra­molecular C—H⋯O hydrogen bonds are observed. In the crystal, mol­ecules are linked into a two-dimensional network parallel to the ab plane by inter­molecular C—H⋯O hydrogen bonds and C—H⋯π inter­actions.

The Novel Pyrrolidine Nor-Lobelane Analog UKCP-110 [cis-2,5-di-(2-phenethyl)-pyrrolidine hydrochloride] Inhibits VMAT2 Function, Methamphetamine-Evoked Dopamine Release, and Methamphetamine Self-Administration in RatsS⃞

Beckmann, Joshua S.; Siripurapu, Kiran B.; Nickell, Justin R.; Horton, David B.; Denehy, Emily D.; Vartak, Ashish; Crooks, Peter A.; Dwoskin, Linda P.; Bardo, Michael T.
Fonte: The American Society for Pharmacology and Experimental Therapeutics Publicador: The American Society for Pharmacology and Experimental Therapeutics
Tipo: Artigo de Revista Científica
Publicado em /12/2010 EN
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Both lobeline and lobelane attenuate methamphetamine self-administration in rats by decreasing methamphetamine-induced dopamine release via interaction with vesicular monoamine transporter-2 (VMAT2). A novel derivative of nor-lobelane, cis-2,5-di-(2-phenethyl)-pyrrolidine hydrochloride (UKCP-110), and its trans-isomers, (2R,5R)-trans-di-(2-phenethyl)-pyrrolidine hydrochloride (UKCP-111) and (2S,5S)-trans-di-(2-phenethyl)-pyrrolidine hydrochloride (UKCP-112), were evaluated for inhibition of [3H]dihydrotetrabenazine binding and [3H]dopamine uptake by using a rat synaptic vesicle preparation to assess VMAT2 interaction. Compounds were evaluated for inhibition of [3H]nicotine and [3H]methyllycaconitine binding to assess interaction with the major nicotinic receptor subtypes. In addition, compounds were evaluated for inhibition of methamphetamine-evoked endogenous dopamine release by using striatal slices. The most promising compound, UKCP-110, was evaluated for its ability to decrease methamphetamine self-administration and methamphetamine discriminative stimulus cues and for its effect on food-maintained operant responding. UKCP-110...

(2R,4R)-1-(tert-But­oxy­carbon­yl)-4-meth­oxy­pyrrolidine-2-carb­oxy­lic acid

Yuan, Jing; Cai, Zhi-Qiang; Huang, Chang-Jiang; Xu, Wei-Ren
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 20/11/2010 EN
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In the title compound, C11H19NO5, the five-membered pyrrolidine ring adopts an envelope conformation. The dihedral angles between the carboxyl group plane, the pyrrolidine ring and the meth­oxy group are 59.50 (3) and 62.02 (1)°, respectively. In the crystal, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules into chains along [100]. The absolute configuration is assigned in accord with that of (2R,4R)-1-(tert-but­oxy­carbon­yl)-4-hy­droxy­pyrrolidine-2-carb­oxy­lic acid, which was the starting material in the synthesis.

Methyl (3R*,3′S*)-1′,1′′-dimethyl-2,2′′-dioxodispiro­[indoline-3,2′-pyrrolidine-3′,3′′-indoline]-4′-carboxyl­ate

Ganesh, G.; Yuvaraj, Panneer Selvam; Govindan, E.; Reddy, Boreddy S. R.; SubbiahPandi, A.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 08/09/2012 EN
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In the title compound, C22H21N3O4, the central pyrrolidine ring adopts an envelope conformation with the N atom in the flap position. The indoline ring systems are almost perpendic­ular to the mean plane of the pyrrolidine ring, making dihedral angles of 86.4 (8) and 83.1 (8)°. The acetate group attached to the pyrrolidine ring assumes an extended conformation. In thecrystal, N—H⋯O hydrogen bonds result in the formation of a C(7) chain running along [100]. The crystal packing also features π–π inter­actions [centroid–centroid distance = 3.2032 (11) Å].

rac-Methyl (1R,3′S)-1′,1′′-dimethyl-2,2′′-dioxo-2H-dispiro­[acenaphthyl­ene-1,2′-pyrrolidine-3′,3′′-indoline]-4′-carboxyl­ate

Ganesh, G.; Yuvaraj, Panneer Selvam; Divakara, Chinthalapuri; Reddy, Boreddy S. R.; SubbiahPandi, A.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 12/01/2013 EN
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In the title compound, C26H22N2O4, the pyrrolidine ring adopts a twisted conformation and the other five-membered rings adopt envelope conformations with the spiro C atoms as the flap atoms. The naphthalene ring system of the dihydro­acenaphthyl­ene group forms dihedral angles of 89.2 (9) and 75.5 (6)° with the pyrrolidine and indole rings, respectively. The pyrrolidine ring makes a dihedral angle of 80.1 (9)° with the indole ring. In the crystal, mol­ecules are linked by weak C—H⋯O hydrogen bonds, forming chains along the b-axis direction.

A triclinic polymorph of methyl (3R,3′S)-1′,1′′-dimethyl-2,2′′-dioxodispiro­[indoline-3,2′-pyrrolidine-3′,3′′-indoline]-4′-carboxyl­ate

Ganesh, G.; Yuvaraj, Panneer Selvam; Divakara, Chinthalapuri; Reddy, Boreddy S. R.; SubbiahPandi, A.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 28/11/2012 EN
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27.16%
In the title compound, C22H21N3O4, the central pyrrolidine ring adopts a C-envelope conformation with a C atom 0.6593 (13) Å displaced from the mean plane formed by the remaining ring atoms. The indoline ring systems (r.m.s. devisations of 0.0356 and 0.0547 Å) are almost perpendicular to the mean plane of the pyrrolidine ring, making dihedral angles of 89.7 (6) and 82.5 (6)°. The acetate group attached to the pyrrolidine ring assumes an extended conformation. In the crystal,N—H⋯O and C—H⋯O hydrogen bonds connect adjacent molecules, forming an infinite tape extending along [1-1-1]. The crystal packing is further consolidated by strong π–π inter­actions with a centroid–centroid distance of 3.2585 (8) Å. The title compound is a polymorph of previously reported monoclinic structure [Ganesh et al. (2012 ▶). Acta Cryst. E68, o2902–o2903].

Ethyl 1′′-benzyl-1′-methyl-2′′-oxodi­spiro­[indeno­[1,2-b]quinoxaline-11,3′-pyrrolidine-2′,3′′-indoline]-4′-carboxyl­ate

Kannan, Piskala Subburaman; Lanka, Srinu; Thennarasu, Sathiah; Govindan, Elumalai; SubbiahPandi, Arunachalathevar
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 04/05/2013 EN
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In the title compound, C36H30N4O3, the quinoxaline–indene system is roughly planar, with a maximum deviation from the mean plane of 0.218 Å for the C atom shared with the central pyrrolidine ring. This latter ring forms dihedral angles of 84.54 (7) and 83.91 (8)° with the quinoxaline–indene system and the indole ring, respectively. The central pyrrolidine ring has an envelope conformation with the N atom as the flap, while the pyrrolidine and five-membered rings of the indole group adopt twisted conformation and envelope (with the C atom bearing the quinoxaline–indene system as the flap) conformations, respectively. In the crystal, mol­ecules are linked via weak C—H⋯N hydrogen bonds, forming a chain running along [100].

4′-(1H-Imidazol-2-yl)-3′-[(1H-indol-3-yl)carbon­yl]-1′-methyl-2-oxo­spiro­[indoline-3,2′-pyrrolidine]-3′-carbo­nitrile 0.15-hydrate

Inglebert, S. Antony; Arun, Yuvaraj; Sethusankar, K.; Perumal, Paramasivam T.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 31/08/2013 EN
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In the title compound, C25H20N6O2·0.15H2O, the dihedral angles between the least-squares planes of the indole and pyrrolidine rings and between the oxindole and imidazole rings are 77.66 (7) and 45.31 (7)°, respectively. The pyrrolidine ring and the fused five-membered pyrrolidine ring of the oxindole moiety exhibit twisted conformations. The amide N atom is involved in both intra- and inter­molecular hydrogen bonding, having a bifurcated character. The mol­ecular structure is characterized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(7) ring motif while an inter­molecular N—H⋯O hydrogen bond links the organic and solvent water mol­ecules. In the crystal, N—H⋯N hydrogen bonds generate a zigzag chain running parallel to c-axis direction. The H atoms of the solvent water mol­ecule were not located.

5-Chloro-5′′-(4-chloro­benzyl­idene)-4′-(4-chloro­phen­yl)-1′,1′′-dimethyldi­spiro­[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Farag, I. S. Ahmed; Girgis, Adel S.; Ramadan, A. A.; Moustafa, A. M.; Mabied, Ahmed F.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 28/02/2014 EN
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The racemic title compound, C30H26Cl3N3O2, comprises two spiro links, the first connecting the piperidine and pyrrolidine rings and the other connecting the indole and pyrrolidine rings. The piperidine ring adopts a half-chair conformation, while the pyrrolidine ring has an envelope conformation with the unsubstituted C atom as the flap. The dihedral angles between the two p-Cl-substituted benzene rings and the indole ring are 33.13 (14) and 54.11 (14)°. In the crystal, mol­ecules form inversion dimers through pairs of N—H⋯O hydrogen bonds [graph set R 2 2(8)]. Aromatic C—H⋯O hydrogen bonds extend these dimers into a ribbon structure, enclosing R 2 2(14) ring motifs, along the a-axis direction.

5′′-Benzyl­idene-5-chloro-1′,1′′-dimethyl-4′-phenyl­dispiro­[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Farag, I. S. Ahmed; Girgis, Adel S.; Ramadan, A. A.; Moustafa, A. M.; Tiekink, Edward R. T.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 07/12/2013 EN
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The title compound, C30H28ClN3O2, features two spiro links, one connecting the piperidine and pyrrolidine rings, and the other connecting the pyrrolidine ring and indole residue. The configuration about the ethene bond is E. The piperidine ring adopts a half-chair conformation where the C atom connected to the spiro-C atom lies 0.713 (3) Å out of the plane of the remaining five atoms (r.m.s. deviation = 0.086 Å). The pyrrolidine ring has an envelope conformation with the flap atom being the methyl­ene C atom. Centrosymmetric eight-membered {⋯HNCO}2 amide synthons feature in the crystal packing. These are consolidated into a three-dimensional architecture by phen­yl–pyrrolidine C—H⋯N and chloro­benzene–pyrrolidine-bound phenyl C—H⋯π inter­actions.

5-Chloro-5′′-(4-chloro­benzyl­idene)-4′-(4-chloro­phen­yl)-1′′-ethyl-1′-methyl­dispiro­[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Farag, I. S. Ahmed; Girgis, Adel S.; Ramadan, A. A.; Moustafa, A. M.; Tiekink, Edward R. T.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 14/12/2013 EN
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Two spiro links are found in the title compound, C31H28Cl3N3O2, one connecting the piperidine and pyrrolidine rings, and the other connecting the pyrrolidine ring and indole residue. The piperidine ring adopts a half-chair conformation, in which the C atom connected to the spiro-C atom lies 0.741 (3) Å out of the plane of the remaining five atoms (r.m.s. deviation = 0.053 Å). The pyrrolidine ring has an envelope conformation with the flap atom being the methyl­ene C atom. Centrosymmetric eight-membered {⋯HNCO}2 amide dimers are the most significant feature of the crystal packing. These are connected into layers parallel to (-120) by C—H⋯O and π–π inter­actions between pyrrolidine-bound benzene rings [inter-centroid distance = 3.8348 (15) Å]. Slipped face-to-face inter­actions between the edges of pyrrolidine-bound benzene [shortest C⋯C separation = 3.484 (4) Å] connect the layers into a three-dimensional architecture.

5-Chloro-5′′-[4-(di­methyl­amino)­benzyl­idene]-4′-[4-(di­methyl­amino)­phen­yl]-1′,1′′-di­methyl­dispiro­[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Farag, I. S. Ahmed; Girgis, Adel S.; Ramadan, A. A.; Moustafa, A. M.; Tiekink, Edward R. T.
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 18/12/2013 EN
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The title compound, C34H38ClN5O2, has spiro links connecting the pyrrolidine ring and indole residue, as well as the piperidine and pyrrolidine rings. A half-chair conformation is found for the piperidine ring with the C atom connected to the spiro-C atom lying 0.738 (4) Å out of the plane of the remaining five atoms (r.m.s. deviation = 0.0407 Å). The methyl­ene C atom is the flap in the envelope conformation for the pyrrolidine ring. In the crystal, supra­molecular chains are sustained by alternating eight-membered {⋯HNCO}2 and 14-membered {⋯HC5O}2 synthons. Chains are connected into a three-dimensional network by (pyrrolidine-bound phenyl-meth­yl)C—H⋯π(pyrrolidine-bound phen­yl) edge-to-face inter­actions.

Pyrrolidine nucleotide analogs with a tunable conformation

Poštová Slavětínská, Lenka; Rejman, Dominik; Pohl, Radek
Fonte: Beilstein-Institut Publicador: Beilstein-Institut
Tipo: Artigo de Revista Científica
Publicado em 22/08/2014 EN
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Conformational preferences of the pyrrolidine ring in nucleotide analogs 7–14 were investigated by means of NMR and molecular modeling. The effect of the relative configuration of hydroxy and nucleobase substituents as well as the effect of the alkylation or acylation of the pyrrolidine nitrogen atom on the conformation of the pyrrolidine ring were studied. The results of a conformational analysis show that the alkylation/acylation can be effectively used for tuning the pyrrolidine conformation over the whole pseudorotation cycle.

I. Stereoselective synthesis of pyrrolidine derivatives via reduction of substituted pyrroles ; II. Progress towards the total synthesis of tetrapetalone A; Stereoselective synthesis of pyrrolidine derivatives via reduction of substituted pyrroles; Progress towards the total synthesis of tetrapetalone A

Jiang, Chao (1979 - ); Frontier, Alison J.
Fonte: University of Rochester. Publicador: University of Rochester.
Tipo: Tese de Doutorado Formato: Number of Pages:x, 267 leaves
ENG
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Thesis (Ph. D.)--University of Rochester. Dept. of Chemistry, 2009.; An efficient and diastereoselective heterogeneous catalytic hydrogenation reaction of highly substituted pyrrole systems has been developed to synthesize pyrrolidine derivatives stereoselectively. The substituted pyrroles are limited to certain substitution patterns. The origin of the diastereoselectivity is believed to come from the stereocenters on the side chain. More evidence needs to be found to explain the stereoselectivity. With the diastereoselectivity in the heterogeneous catalytic hydrogenation and the known asymmetric reduction of ketones and imines, a convenient enantioselective protocol for the reduction of substituted pyrroles is promising. Tetrapetalone A, was targeted for synthesis due to its novel tetracyclic skeletal structure. The 5-6 fused bicyclic core could be accessed via a polarized Nazarov reaction, and this bicyclic core was converted into an aryl triflate in order to test transition metal-catalyzed coupling reactions to form the C-N bond. The intermolecular cross-coupling reactions between the bicyclic aryl triflate of tetrapetalone A and different nitrogen nucleophiles showed that the steric hindrance from both coupling partners had a strong impact on the efficiency of the C-N bond formation...

(R,R)-N-phenyl-3,4-bis(diphenylphosphino)pyrrolidine: an N-aryl pyrrolidine ligand for enantioselective transfer hydrogenation

Gonsalves, António Manuel d'Albuquerque Rocha; Serra, Maria Elisa da Silva; Silva, Manuela Ramos; Beja, Ana Matos; Paixão, José António; Veiga, Luiz Alte da
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
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The N-aryl pyrrolidine diphosphine (R,R)-N-phenyl-3,4-bis(diphenylphosphino)pyrrolidine was obtained from natural tartaric acid. Contrary to our preliminary expectations, this new chiral ligand proved to be less selective than the corresponding N-benzyl pyrrolidine diphosphine. An attempted explanation of the observed behaviour based on the stereochemistry of the ligand as shown by X-ray crystallography is presented.; http://www.sciencedirect.com/science/article/B6TGM-42G6XGY-8/1/25fa9c4e0f48edebc992db1e0b302bf0

Design, Synthesis, and Structural Analysis of Influenza Neuraminidase Inhibitors Containing Pyrrolidine cores

Wang, Gary; Chen, Yuanwei; Wang, Sheldon; Gentles, Andrew J; Sowin, Thomas; Kati, Warren; Muchmore, Steven; Giranda, Vincent; Stewart, Kent; Sham, Hing; Kempf, Dale; Laver, W. Graeme
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica
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The discovery of (±)-(2S,3R,4R)-2-(trifluoroacetamido)methyl-3-amino-1- (N′-ethyl-N′-isopropylcarbamyl)pyrrolidine-4-carboxylic acid (A-192558, 20e) as a potent inhibitor of influenza neuraminidase (NA) is described. Efficient syntheses of two core s