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1.
Mar Drugs ; 17(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366127

RESUMO

Preussin, a hydroxyl pyrrolidine derivative isolated from the marine sponge-associated fungus Aspergillus candidus KUFA 0062, displayed anticancer effects in some cancer cell lines, including MCF7. Preussin was investigated for its cytotoxic and antiproliferative effects in breast cancer cell lines (MCF7, SKBR3, and MDA-MB-231), representatives of major breast cancers subtypes, and in a non-tumor cell line (MCF12A). Preussin was first tested in 2D (monolayer), and then in 3D (multicellular aggregates), cultures, using a multi-endpoint approach for cytotoxicity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), resazurin and lactate dehydrogenase (LDH)) and proliferative (5-bromo-2'-deoxyuridine (BrdU)) assays, as well as the analysis of cell morphology by optical/electron microscopy and immunocytochemistry for caspase-3 and ki67. Preussin affected cell viability and proliferation in 2D and 3D cultures in all cell lines tested. The results in the 3D culture showed the same tendency as in the 2D culture, however, cells in the 3D culture were less responsive. The effects were observed at different concentrations of preussin, depending on the cell line and assay method. Morphological study of preussin-exposed cells revealed cell death, which was confirmed by caspase-3 immunostaining. In view of the data, we recommend a multi-endpoint approach, including histological evaluation, in future assays with the tested 3D models. Our data showed cytotoxic and antiproliferative activities of preussin in breast cancer cell lines in 2D and 3D cultures, warranting further studies for its anticancer potential.


Assuntos
Anisomicina/análogos & derivados , Antineoplásicos/farmacologia , Aspergillus/química , Neoplasias da Mama/tratamento farmacológico , Poríferos/microbiologia , Animais , Anisomicina/farmacologia , Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7
2.
Org Biomol Chem ; 17(1): 122-134, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30520931

RESUMO

Short syntheses of oxa-preussin, racemic preussin and (-)-preussin are reported. Starting from a racemic 3-nonyl-substituted methoxyallene derivative, its lithiation and addition to phenylethanal provided the corresponding allenyl alcohol that was converted into two diastereomeric dihydrofuran derivatives by silver nitrate-catalyzed 5-endo-trig cyclization. The acid hydrolysis of the enol ether moiety gave heterocyclic ketones and subsequent highly stereoselective reductions with l-selectride furnished 2-benzyl-5-nonylfuran-3-ol derivatives in good overall yield. The major all-cis-diastereomer has the skeleton and relative configuration of preussin and is hence called oxa-preussin. An analogous sequence with the same allene, but an N-sulfonyl imine as the electrophile, finally led to racemic preussin. The stereoselectivities of the individual steps are discussed in detail. With an enantiopure 2-benzyl-5-nonylpyrrolidin-3-one intermediate the preparation of (-)-preussin with an enantiomeric ratio of >95 : 5 could be accomplished in a few steps. The sign of the optical rotation of this product finally proved the absolute configurations of its precursors and demonstrated that our chiral auxiliary-based route led to the antipode of the natural product. The cytotoxicity of several of the prepared heterocycles against MCF-7 tumor cells was investigated and five compounds, including racemic and enantiopure (-)-preussin, were identified as highly cytotoxic with IC50 values in the range of 3-6 µM.


Assuntos
Alcadienos/química , Anisomicina/análogos & derivados , Álcoois , Anisomicina/síntese química , Anisomicina/toxicidade , Catálise , Citotoxinas/síntese química , Humanos , Hidrólise , Concentração Inibidora 50 , Cetonas , Células MCF-7 , Estereoisomerismo
3.
J Nat Prod ; 81(10): 2275-2281, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30350993

RESUMO

New pyrrolidine alkaloids, preussins C-I (1-7) and (11 R)/(11 S)-preussins J and K (8 and 9), were isolated from the sponge-derived fungus Aspergillus flocculosus 16D-1. The structures and configurations of these preussins were elucidated by detailed spectroscopic analysis, modified Mosher's method, and comparisons with literature data. These compounds showed strong to moderate inhibitory activity toward IL-6 production in lipopolysaccharide-induced THP-1 cells with IC50 values ranging from 0.11 to 22 µM, but were inactive against normal tumor cell lines and fungi.


Assuntos
Anisomicina/análogos & derivados , Aspergillus/química , Interleucina-6/antagonistas & inibidores , Poríferos/microbiologia , Animais , Anisomicina/isolamento & purificação , Anisomicina/farmacologia , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Linhagem Celular , Humanos , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética
4.
Mar Drugs ; 16(4)2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29642369

RESUMO

A previously unreported bis-indolyl benzenoid, candidusin D (2e) and a new hydroxypyrrolidine alkaloid, preussin C (5b) were isolated together with fourteen previously described compounds: palmitic acid, clionasterol, ergosterol 5,8-endoperoxides, chrysophanic acid (1a), emodin (1b), six bis-indolyl benzenoids including asterriquinol D dimethyl ether (2a), petromurin C (2b), kumbicin B (2c), kumbicin A (2d), 2″-oxoasterriquinol D methyl ether (3), kumbicin D (4), the hydroxypyrrolidine alkaloid preussin (5a), (3S, 6S)-3,6-dibenzylpiperazine-2,5-dione (6) and 4-(acetylamino) benzoic acid (7), from the cultures of the marine sponge-associated fungus Aspergillus candidus KUFA 0062. Compounds 1a, 2a-e, 3, 4, 5a-b, and 6 were tested for their antibacterial activity against Gram-positive and Gram-negative reference and multidrug-resistant strains isolated from the environment. Only 5a exhibited an inhibitory effect against S. aureus ATCC 29213 and E. faecalis ATCC29212 as well as both methicillin-resistant S. aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains. Both 1a and 5a also reduced significant biofilm formation in E. coli ATCC 25922. Moreover, 2b and 5a revealed a synergistic effect with oxacillin against MRSA S. aureus 66/1 while 5a exhibited a strong synergistic effect with the antibiotic colistin against E. coli 1410/1. Compound 1a, 2a-e, 3, 4, 5a-b, and 6 were also tested, together with the crude extract, for cytotoxic effect against eight cancer cell lines: HepG2, HT29, HCT116, A549, A 375, MCF-7, U-251, and T98G. Except for 1a, 2a, 2d, 4, and 6, all the compounds showed cytotoxicity against all the cancer cell lines tested.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Aspergillus/química , Bactérias/efeitos dos fármacos , Poríferos/microbiologia , Animais , Anisomicina/análogos & derivados , Anisomicina/química , Anisomicina/isolamento & purificação , Anisomicina/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Farmacorresistência Bacteriana/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Pirrolidinas/química , Pirrolidinas/isolamento & purificação , Pirrolidinas/farmacologia , Compostos de Terfenil/química , Compostos de Terfenil/isolamento & purificação
5.
Org Biomol Chem ; 15(3): 649-661, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-27973631

RESUMO

A diastereoselective approach to trans-4-hydroxy-5-substituted 2-pyrrolidinones 1 (P1 = TBS, P2 = H) has been developed through a stereoselective tandem Barbier process of (R,SRS)-8 with alkyl and aryl bromide. The stereochemistry at the C-5 stereogenic center of the trans-4-hydroxy-5-substituted 2-pyrrolidinones was solely controlled by α-alkoxy substitution. This effective approach was successfully used to prepare a variety of substituted (3R,4S)-statines 2. In addition, two bioactive natural products of (+)-preussin 4 and hapalosin 5 were effectively synthesized through this stereoselective tandem Barbier process.


Assuntos
Aminoácidos/síntese química , Anisomicina/análogos & derivados , Depsipeptídeos/síntese química , Lactamas/síntese química , Lactonas/síntese química , Pirrolidinonas/síntese química , Aminoácidos/química , Anisomicina/síntese química , Anisomicina/química , Depsipeptídeos/química , Lactamas/química , Lactonas/química , Conformação Molecular , Pirrolidinonas/química , Estereoisomerismo
6.
J Org Chem ; 79(14): 6748-53, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24979222

RESUMO

A straightforward and stereoselective synthesis of the alkaloid preussin is described starting from decanal and diethyl 3-diazo-2-oxopropylphosphonate. The key steps are an aza-Michael reaction from an α,ß-unsaturated diazoketone followed by a highly stereoselective Cu-catalyzed ylide formation and then a [1,2]-Stevens rearrangement. This strategy is feasible for extension to preussin analogues, demonstrating its utility for the rapid construction of all-cis-substituted pyrrolidines.


Assuntos
Aldeídos/química , Anisomicina/análogos & derivados , Anisomicina/síntese química , Anisomicina/química , Estrutura Molecular , Estereoisomerismo
7.
J Nat Prod ; 77(4): 813-7, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24588303

RESUMO

A new pyrrolidine alkaloid, preussin B (1), was isolated from the culture extract of the fungus Simplicillium lanosoniveum TAMA 173 along with the known congener preussin (2). The structure and absolute configuration of 1 were determined by spectroscopic analysis and spectral comparison with 2. Feeding experiments with 13C-labeled precursors revealed that the pyrrolidine ring of 1 was assembled from acetate and l-phenylalanine by a PKS-NRPS hybrid biosynthetic pathway.


Assuntos
Anisomicina/análogos & derivados , Hypocreales/química , Alcaloides/biossíntese , Alcaloides/metabolismo , Anisomicina/química , Anisomicina/isolamento & purificação , Estrutura Molecular , Complexos Multienzimáticos/biossíntese , Complexos Multienzimáticos/metabolismo , Peptídeo Sintases/biossíntese , Peptídeo Sintases/química , Peptídeo Sintases/metabolismo , Fenilalanina/biossíntese , Fenilalanina/metabolismo , Estereoisomerismo , Streptomyces/metabolismo
8.
Biochem Biophys Res Commun ; 443(2): 761-7, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24333448

RESUMO

Anisomycin was identified in a screen of clinical compounds as a drug that kills breast cancer cells (MDA16 cells, derived from the triple negative breast cancer cell line, MDA-MB-468) that express high levels of an efflux pump, ABCB1. We show the MDA16 cells died by a caspase-independent mechanism, while MDA-MB-468 cells died by apoptosis. There was no correlation between cell death and either protein synthesis or JNK activation, which had previously been implicated in anisomycin-induced cell death. In addition, anisomycin analogues that did not inhibit protein synthesis or activate JNK retained the ability to induce cell death. These data suggest that either a ribosome-ANS complex is a death signal in the absence of JNK activation or ANS kills cells by binding to an as yet unidentified target.


Assuntos
Anisomicina/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , MAP Quinase Quinase 4/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Anisomicina/análogos & derivados , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Humanos
10.
Org Lett ; 12(18): 4034-7, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20726562

RESUMO

A convergent and stereoselective synthesis of 2,5-disubstituted 3-hydroxypyrrolidines has been developed that involves reductive annulation of ß-iminochlorohydrins, which are readily available from ß-ketochlorohydrins, and provides rapid access to a variety of 2,5-syn-pyrrolidines. Application of this process to the concise (three-step) synthesis of the fungal metabolite (+)-preussin and analogues of this substance is reported.


Assuntos
Anisomicina/análogos & derivados , Anisomicina/síntese química , Estrutura Molecular , Estereoisomerismo , Fatores de Tempo
11.
Org Lett ; 11(15): 3270-3, 2009 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-19580247

RESUMO

(S)-N-(2-pyrrolidinylmethyl)pyrrolidine/trifluoroacetic acid (3:1) combination catalyzed the direct addition of alkyl methyl ketones to beta-dimethyl(phenyl)silylmethylene malonate at the methyl terminal with high yield and excellent regio- and enantioselectivity. The silyl group played crucial roles in regioselection and substrate reactivity.


Assuntos
Anisomicina/análogos & derivados , Cetonas/química , Malonatos/química , Oxazolidinonas/química , Acetona/química , Anisomicina/síntese química , Anisomicina/química , Catálise , Pirrolidinas/química
12.
Org Lett ; 10(7): 1433-6, 2008 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-18331047

RESUMO

Pyrrolidine enones, derived from 3-oxo pyrrolidine 2-phosphonates and a HWE reaction with aldehydes, on Luche reduction give pyrrolidine allylic alcohols. The alcohols on hydrogenation (Pd/H2) give cis-2,5-disubstituted pyrrolidines and on treatment with TFA-NaBH3CN undergo a hydroxy directed reduction to trans-2,5-disubstituted pyrrolidines.


Assuntos
Anisomicina/análogos & derivados , Organofosfonatos/química , Pirrolidinas/síntese química , Anisomicina/síntese química , Anisomicina/química , Catálise , Pirrolidinas/química , Estereoisomerismo
13.
Bioconjug Chem ; 18(5): 1593-603, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17705414

RESUMO

Two approaches to the synthesis of biotinylated derivatives of the stress-activated protein kinase (SAPK) pathway activator anisomycin have been investigated. Attachment of the biotin moiety to the central core was achieved either through the use of a classical displacement reaction on alpha-halo carbonyl derivatives of biotin or through a copper(I)-catalyzed 1,3-dipolar Huisgen cycloaddition ("click") coupling of biotinylated azides to propargyl-marked analogues of anisomycin. In each case, the resultant N-linked molecular probes were found to be active in SAPK pathway immunoblot assays, while their O-linked counterparts were inactive. However, in sharp contrast to the classical coupling approach which results in low coupling yields, the aqueous "click" coupling process was found to deliver high yields of biotinylated probes, making it the conjugation method of choice. A survey of the available methods for the addition of a propargyl marker onto a range of chemical functionalities strongly suggests that this copper(I)-catalyzed 1,3-dipolar Huisgen cycloaddition approach to biotinylation may be generally applied.


Assuntos
Anisomicina/síntese química , Antibacterianos/química , Técnicas de Química Combinatória/métodos , Proteínas Quinases/metabolismo , Anisomicina/análogos & derivados , Anisomicina/farmacologia , Antibacterianos/farmacologia , Azidas/química , Biotinilação , Catálise , Cobre/química , Immunoblotting/métodos , Estrutura Molecular , Estresse Oxidativo , Pargilina/química
14.
Org Biomol Chem ; 5(4): 636-43, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17285172

RESUMO

A truncated approach to the design of molecular probes from small molecule libraries is outlined, based upon the incorporation of a bioorthogonal marker. The applicability of this strategy to small molecule chemical genetics screens has been demonstrated using analogues of the known stress activated protein kinase (SAPK) pathway activator, anisomycin. Compounds marked with a propargyl group have shown activation of the SAPK pathways comparable to that induced by their parent structures, as demonstrated by immunoblot assays against the downstream target JNK1/2. The considerable advantages of this new approach to molecular probe design have been illustrated through the rapid development of a functionally active fluorescent molecular probe, through coupling of the marked analogues to fluorescent azides using the copper(i)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction. Active molecular probes generated in this study were used to investigate cellular uptake through FACS analysis and confocal microscopy.


Assuntos
Azidas/química , Técnicas de Química Combinatória/métodos , Sondas Moleculares/química , Anisomicina/análogos & derivados , Anisomicina/farmacologia , Azidas/síntese química , Azidas/farmacologia , Catálise , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Cobre/química , Humanos , Proteína Quinase 8 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 9 Ativada por Mitógeno/antagonistas & inibidores , Conformação Molecular , Sondas Moleculares/síntese química , Sondas Moleculares/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
15.
Org Lett ; 8(11): 2353-6, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16706524

RESUMO

[reaction: see text] A new stereoselective synthesis of the antifungal and antitumor agents Preussin and 3-epi-Preussin via a Pd-catalyzed carboamination of a protected amino alcohol is described. The key transformation leads to simultaneous formation of the N-C2 bond and the C1'-aryl bond, and allows installation of the aryl group one step from the end of the sequence. This strategy permits the facile construction of a variety of preussin analogues bearing different aromatic groups.


Assuntos
Anisomicina/análogos & derivados , Antifúngicos/química , Antifúngicos/síntese química , Antineoplásicos/química , Antineoplásicos/síntese química , Anisomicina/síntese química , Anisomicina/química , Aspergillus/química , Técnicas de Química Combinatória , Estrutura Molecular , Paládio/química , Estereoisomerismo
16.
J Org Chem ; 70(10): 4082-7, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15876100

RESUMO

[structures: see text] Enantiomerically pure 2-alkyl-3-acetoxy-4-iodopyrrolidines with all groups cis, and all adjacent groups trans (10 and 17), important precursors for the synthesis of pyrrolidinediols, have been prepared from D-tyrosine through regio- and diastereoselective reduction of a vinyl ketone and subsequent iodoamidation controlled by minimization of nonbonding steric interactions. Highly stereodivergent Woodward-Prevost methodology, applied to both iodopyrrolidines, yielded enantiomerically pure (2R,3R,4R)-, (2R,3R,4S)-, and (2R,3S,4R)-deacetylanisomycin (3, 4, and 5), each in excellent de. Incorporation of differential protection of the hydroxyl groups led to a one-pot synthesis of (2R,3R,4R)-anisomycin 2.


Assuntos
Anisomicina/análogos & derivados , Anisomicina/síntese química , Tirosina/química , Anisomicina/química , Estereoisomerismo
17.
Org Biomol Chem ; 2(1): 142-9, 2004 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-14737674

RESUMO

The synthesis of C(4)H and C(4)Me analogues of the JNK/p38 pathway activator anisomycin, based upon an aldol or Claisen construction of the C(3)-C(4) bond, has been demonstrated. The relative activation of the JNK/SAPK1 and p38/SAPK2 pathways in RAW macrophages by these analogues, and their synthetic precursors, has been assessed using immunoblot assays against phosphorylated c-Jun and MAPKAP-K2. These studies demonstrate that some of the synthetic C(4) analogues are also potent activators of these stress kinase pathways.


Assuntos
Anisomicina/análogos & derivados , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Anisomicina/síntese química , Anisomicina/química , Linhagem Celular , Ativação Enzimática , Sistema de Sinalização das MAP Quinases , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Proteína Quinase 8 Ativada por Mitógeno , Proteínas Quinases p38 Ativadas por Mitógeno
18.
Virology ; 300(1): 60-70, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12202206

RESUMO

Many viruses use programmed -1 ribosomal frameshifting to ensure the correct ratio of viral structural to enzymatic proteins. Alteration of frameshift efficiencies changes these ratios, in turn inhibiting viral particle assembly and virus propagation. Previous studies determined that anisomycin, a peptidyl transferase inhibitor, specifically inhibited -1 frameshifting and the ability of yeast cells to propagate the L-A and M(1) dsRNA viruses (J. D. Dinman, M. J. Ruiz-Echevarria, K. Czaplinski, and S. W. Peltz, 1997, Proc. Natl. Acad. Sci. USA 94, 6606-6611). Here we show that preussin, a pyrollidine that is structurally similar to anisomycin (R. E. Schwartz, J. Liesch, O. Hensens, L. Zitano, S. Honeycutt, G. Garrity, R. A. Fromtling, J. Onishi, and R. Monaghan, 1988. J. Antibiot. (Tokyo) 41, 1774--1779), also inhibits -1 programmed ribosomal frameshifting and virus propagation by acting at the same site or through the same mechanism as anisomycin. Since anisomycin is known to assert its effect at the ribosomal A-site, we undertook a pharmacogenetic analysis of mutants of trans-acting eukaryotic elongation factors (eEFs) that function at this region of the ribosome. Among mutants of eEF1A, a correlation is observed between resistance/susceptibility profiles to preussin and anisomycin, and these in turn correlate with programmed -1 ribosomal frameshifting efficiencies and killer virus phenotypes. Among mutants of eEF2, the extent of resistance to preussin correlates with resistance to sordarin, an eEF2 inhibitor. These results suggest that structural features associated with the ribosomal A-site and with the trans-acting factors that interact with it may present a new set of molecular targets for the rational design of antiviral compounds.


Assuntos
Anisomicina/análogos & derivados , Anisomicina/farmacologia , Antivirais/química , Proteínas Ribossômicas/efeitos dos fármacos , Ribossomos/efeitos dos fármacos , Saccharomyces cerevisiae/virologia , Anisomicina/química , Antivirais/síntese química , Desenho de Fármacos , Mutação da Fase de Leitura/efeitos dos fármacos , Genótipo , Cinética , Modelos Moleculares , Fator G para Elongação de Peptídeos/química , Fator G para Elongação de Peptídeos/genética , Estrutura Secundária de Proteína , Saccharomyces cerevisiae/genética , Relação Estrutura-Atividade , Fatores de Tempo
19.
Biosci Biotechnol Biochem ; 66(5): 1093-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12092820

RESUMO

All the eight stereoisomers of (+)-preussin (1b), an antifungal agent inhibiting the growth of fission yeast and human cancer cells, were synthesized in two steps by non-stereoselective reactions and chromatographic separation, starting from L- and D-N-protected-phenylalaninal (2). Their bioassay revealed all of the stereoisomers to be almost equally bioactive.


Assuntos
Anisomicina/análogos & derivados , Anisomicina/síntese química , Anisomicina/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Anisomicina/química , Antifúngicos/química , Espectroscopia de Ressonância Magnética , Schizosaccharomyces/efeitos dos fármacos , Estereoisomerismo
20.
Org Lett ; 2(25): 4041-2, 2000 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11112638

RESUMO

[structure] The enantioselective total synthesis of (+)-preussin, a potent antifungal agent, has been achieved. The key steps are a Pd(0)-catalyzed oxazoline-forming reaction from L-phenylalanine, hydrogenolysis, and subsequent diastereoselective reductive cyclization of the intermediate aminoketone to pyrrolidine using Pearlman's catalyst.


Assuntos
Anisomicina/análogos & derivados , Antifúngicos/síntese química , Anisomicina/síntese química , Catálise , Ciclização , Hidrogenação , Oxazóis/síntese química , Oxazóis/química , Oxirredução , Paládio , Fenilalanina/química , Estereoisomerismo
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