Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry
Autor(a) principal: | |
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Data de Publicação: | 2002 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/1822/72937 |
Resumo: | Sulfur analogues of dehydrotryptophan (5-7) were prepared in moderate to good yields (40-80%) by Suzuki cross coupling [Pd(PPh3)(4), Na2CO3 or NaHCO3, DME/H2O, 90 degreesC] of several benzo[b]thiophene boronic acids with the methyl esters of N-tert-butyloxycarbonyl-beta-bromodehydroalanine [Boc-DeltaAla(beta-Br)-OMe] or N-tert-butyloxycarbonyl-beta-bromodehydroaminobutyric acid [Boc-DeltaAbu(beta-Br)-OMe]. The beta-bromodehydroaminoacid precursors 2 were, in turn, synthesized in high yields from the corresponding N,N-diacyldehydroamino acids 1 by treatment with trifluoroacetic acid (TFA) and N-bromosuccinimide (NBS) in two steps or in a one-pot procedure. Both procedures were stereoselective for the E-isomer of Boc-DeltaAla(beta-Br)-OMe. However, for Boc-DeltaAbu(beta-Br)-OMe, different ratios of E/Z isomers were obtained in each procedure. The stereoselectivity for the Z-isomer was increased greatly with the one-pot procedure. Pure isomers were used in the coupling reactions and the stereochemistry of the starting material was generally maintained. |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistryAmino acidsSulfur heterocyclesSuzuki couplingStereoisomerismScience & TechnologySulfur analogues of dehydrotryptophan (5-7) were prepared in moderate to good yields (40-80%) by Suzuki cross coupling [Pd(PPh3)(4), Na2CO3 or NaHCO3, DME/H2O, 90 degreesC] of several benzo[b]thiophene boronic acids with the methyl esters of N-tert-butyloxycarbonyl-beta-bromodehydroalanine [Boc-DeltaAla(beta-Br)-OMe] or N-tert-butyloxycarbonyl-beta-bromodehydroaminobutyric acid [Boc-DeltaAbu(beta-Br)-OMe]. The beta-bromodehydroaminoacid precursors 2 were, in turn, synthesized in high yields from the corresponding N,N-diacyldehydroamino acids 1 by treatment with trifluoroacetic acid (TFA) and N-bromosuccinimide (NBS) in two steps or in a one-pot procedure. Both procedures were stereoselective for the E-isomer of Boc-DeltaAla(beta-Br)-OMe. However, for Boc-DeltaAbu(beta-Br)-OMe, different ratios of E/Z isomers were obtained in each procedure. The stereoselectivity for the Z-isomer was increased greatly with the one-pot procedure. Pure isomers were used in the coupling reactions and the stereochemistry of the starting material was generally maintained.The Foundation for Science and Technology (Portugal) is thanked for financial support through IBQF-Univ. Minho, POCTI/99/QUI/32689 project (also financial support of N.O. Silva) and through SFRH/BD/4709/2001 (PhD financial support of A.S. Abreu)WileyUniversidade do MinhoSilva, Natália O.Abreu, Ana S.Ferreira, Paula M. T.Monteiro, Luís S.Queiroz, Maria João R. P.2002-082002-08-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/72937eng1434-193X1099-069010.1002/1099-0690(200208)2002:15<2524::AID-EJOC2524>3.0.CO;2-Whttps://chemistry-europe.onlinelibrary.wiley.com/journal/10990690info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T12:40:51ZPortal AgregadorONG |
dc.title.none.fl_str_mv |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
title |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
spellingShingle |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry Silva, Natália O. Amino acids Sulfur heterocycles Suzuki coupling Stereoisomerism Science & Technology |
title_short |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
title_full |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
title_fullStr |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
title_full_unstemmed |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
title_sort |
Synthesis using Suzuki cross couplings of sulfur analogues of dehydrotryptophan with a definite stereochemistry |
author |
Silva, Natália O. |
author_facet |
Silva, Natália O. Abreu, Ana S. Ferreira, Paula M. T. Monteiro, Luís S. Queiroz, Maria João R. P. |
author_role |
author |
author2 |
Abreu, Ana S. Ferreira, Paula M. T. Monteiro, Luís S. Queiroz, Maria João R. P. |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade do Minho |
dc.contributor.author.fl_str_mv |
Silva, Natália O. Abreu, Ana S. Ferreira, Paula M. T. Monteiro, Luís S. Queiroz, Maria João R. P. |
dc.subject.por.fl_str_mv |
Amino acids Sulfur heterocycles Suzuki coupling Stereoisomerism Science & Technology |
topic |
Amino acids Sulfur heterocycles Suzuki coupling Stereoisomerism Science & Technology |
description |
Sulfur analogues of dehydrotryptophan (5-7) were prepared in moderate to good yields (40-80%) by Suzuki cross coupling [Pd(PPh3)(4), Na2CO3 or NaHCO3, DME/H2O, 90 degreesC] of several benzo[b]thiophene boronic acids with the methyl esters of N-tert-butyloxycarbonyl-beta-bromodehydroalanine [Boc-DeltaAla(beta-Br)-OMe] or N-tert-butyloxycarbonyl-beta-bromodehydroaminobutyric acid [Boc-DeltaAbu(beta-Br)-OMe]. The beta-bromodehydroaminoacid precursors 2 were, in turn, synthesized in high yields from the corresponding N,N-diacyldehydroamino acids 1 by treatment with trifluoroacetic acid (TFA) and N-bromosuccinimide (NBS) in two steps or in a one-pot procedure. Both procedures were stereoselective for the E-isomer of Boc-DeltaAla(beta-Br)-OMe. However, for Boc-DeltaAbu(beta-Br)-OMe, different ratios of E/Z isomers were obtained in each procedure. The stereoselectivity for the Z-isomer was increased greatly with the one-pot procedure. Pure isomers were used in the coupling reactions and the stereochemistry of the starting material was generally maintained. |
publishDate |
2002 |
dc.date.none.fl_str_mv |
2002-08 2002-08-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/1822/72937 |
url |
http://hdl.handle.net/1822/72937 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
1434-193X 1099-0690 10.1002/1099-0690(200208)2002:15<2524::AID-EJOC2524>3.0.CO;2-W https://chemistry-europe.onlinelibrary.wiley.com/journal/10990690 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Wiley |
publisher.none.fl_str_mv |
Wiley |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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repository.mail.fl_str_mv |
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1777303816445624320 |