Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides
Autor(a) principal: | |
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Data de Publicação: | 2005 |
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/1822/3475 |
Resumo: | Accurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alfa,alfa-trialkyl glycine cyclohexyl amides in TFA were performed at 25.00 ºC and the reactions monitored by HPLC. The results were in all cases consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with this data between rate constant values and structure, but a good correlation coefficient was obtained when a multiple regression analysis was applied by taking advantage of a Taft equation using appropriate polar and steric substituent parameters. In a plot of the values observed for log k against those calculated by this equation all five points fell very close to the line of perfect correlation. The calculated sensitivity coefficients to polar and steric contributions were used to discuss the experimental results and showed that the acidolyses are comparatively less affected by steric effects than what one would expect. |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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7160 |
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Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amidesSelective acidolysisN-acyl-N,alfa,alfa-trialkyl glycine amidesN-acyl-N,alpha,alpha-trialkyl glycine amidesrate constantsTaft equationspolar and steric substituent parametersScience & TechnologyAccurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alfa,alfa-trialkyl glycine cyclohexyl amides in TFA were performed at 25.00 ºC and the reactions monitored by HPLC. The results were in all cases consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with this data between rate constant values and structure, but a good correlation coefficient was obtained when a multiple regression analysis was applied by taking advantage of a Taft equation using appropriate polar and steric substituent parameters. In a plot of the values observed for log k against those calculated by this equation all five points fell very close to the line of perfect correlation. The calculated sensitivity coefficients to polar and steric contributions were used to discuss the experimental results and showed that the acidolyses are comparatively less affected by steric effects than what one would expect.Fundação para a Ciência e Tecnologia - SFRH/BPD/1544/2000.John Wiley and SonsUniversidade do MinhoJiang, Wie QunLima, Sílvia M. M. A. PereiraVentura, CristinaCosta, Susana P. G.Albuquerque, LídiaMaia, Raquel M. GonçalvesMaia, Hernâni L. S.20052005-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/3475eng"Journal of Peptide Science". ISSN 1099-1387. 11 (2005) 627-632.1099-138710.1002/psc.67315988788http://www3.interscience.wiley.com/cgi-bin/jhome/6016info: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:RCAAP2023-07-21T12:06:26Zoai:repositorium.sdum.uminho.pt:1822/3475Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T18:57:06.662704Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
title |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
spellingShingle |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides Jiang, Wie Qun Selective acidolysis N-acyl-N,alfa,alfa-trialkyl glycine amides N-acyl-N,alpha,alpha-trialkyl glycine amides rate constants Taft equations polar and steric substituent parameters Science & Technology |
title_short |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
title_full |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
title_fullStr |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
title_full_unstemmed |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
title_sort |
Kinetic investigation of the effect of the amino acid side chains in the selective acidolysis of N-acyl-N,alfa,alfa-trialkyl glycine amides |
author |
Jiang, Wie Qun |
author_facet |
Jiang, Wie Qun Lima, Sílvia M. M. A. Pereira Ventura, Cristina Costa, Susana P. G. Albuquerque, Lídia Maia, Raquel M. Gonçalves Maia, Hernâni L. S. |
author_role |
author |
author2 |
Lima, Sílvia M. M. A. Pereira Ventura, Cristina Costa, Susana P. G. Albuquerque, Lídia Maia, Raquel M. Gonçalves Maia, Hernâni L. S. |
author2_role |
author author author author author author |
dc.contributor.none.fl_str_mv |
Universidade do Minho |
dc.contributor.author.fl_str_mv |
Jiang, Wie Qun Lima, Sílvia M. M. A. Pereira Ventura, Cristina Costa, Susana P. G. Albuquerque, Lídia Maia, Raquel M. Gonçalves Maia, Hernâni L. S. |
dc.subject.por.fl_str_mv |
Selective acidolysis N-acyl-N,alfa,alfa-trialkyl glycine amides N-acyl-N,alpha,alpha-trialkyl glycine amides rate constants Taft equations polar and steric substituent parameters Science & Technology |
topic |
Selective acidolysis N-acyl-N,alfa,alfa-trialkyl glycine amides N-acyl-N,alpha,alpha-trialkyl glycine amides rate constants Taft equations polar and steric substituent parameters Science & Technology |
description |
Accurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alfa,alfa-trialkyl glycine cyclohexyl amides in TFA were performed at 25.00 ºC and the reactions monitored by HPLC. The results were in all cases consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with this data between rate constant values and structure, but a good correlation coefficient was obtained when a multiple regression analysis was applied by taking advantage of a Taft equation using appropriate polar and steric substituent parameters. In a plot of the values observed for log k against those calculated by this equation all five points fell very close to the line of perfect correlation. The calculated sensitivity coefficients to polar and steric contributions were used to discuss the experimental results and showed that the acidolyses are comparatively less affected by steric effects than what one would expect. |
publishDate |
2005 |
dc.date.none.fl_str_mv |
2005 2005-01-01T00:00:00Z |
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/1822/3475 |
url |
http://hdl.handle.net/1822/3475 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
"Journal of Peptide Science". ISSN 1099-1387. 11 (2005) 627-632. 1099-1387 10.1002/psc.673 15988788 http://www3.interscience.wiley.com/cgi-bin/jhome/6016 |
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 |
John Wiley and Sons |
publisher.none.fl_str_mv |
John Wiley and Sons |
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) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799132359829749760 |