C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol
Autor(a) principal: | |
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Data de Publicação: | 2011 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Journal of the Brazilian Chemical Society (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532011000500026 |
Resumo: | The C-24 configurations of (22E)-24-ethyl-24-methylcholesta-5,22-dien-3β-ol (1) and 24-ethyl-24-methylcholest-5-en-3β-ol (2), isolated from the Colombian Caribbean sponge Topsentia ophiraphidites, were determined to be R and S, respectively, by comparing their NMR data with those of stereodefined (24R)- and (24S)-samples that were synthesized in routes involving the orthoester Claisen rearrangement of Δ23-22-allylic alcohols. This is the first synthetic study where the Claisen rearrangement is used to introduce a C-24 quaternary center in a stereospecific manner with acceptable yield. X-ray analysis of 1 confirmed these stereochemical assignments. |
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C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol24-ethyl-24-methylcholesterol24-ethyl-24-methylcholesta-5,22-dien-3b-olTopsentia ophiraphiditesmarine sterolorthoester Claisen rearrangementThe C-24 configurations of (22E)-24-ethyl-24-methylcholesta-5,22-dien-3β-ol (1) and 24-ethyl-24-methylcholest-5-en-3β-ol (2), isolated from the Colombian Caribbean sponge Topsentia ophiraphidites, were determined to be R and S, respectively, by comparing their NMR data with those of stereodefined (24R)- and (24S)-samples that were synthesized in routes involving the orthoester Claisen rearrangement of Δ23-22-allylic alcohols. This is the first synthetic study where the Claisen rearrangement is used to introduce a C-24 quaternary center in a stereospecific manner with acceptable yield. X-ray analysis of 1 confirmed these stereochemical assignments.Sociedade Brasileira de Química2011-05-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532011000500026Journal of the Brazilian Chemical Society v.22 n.5 2011reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50532011000500026info:eu-repo/semantics/openAccessEchigo,ShizueCastellanos,LeonardoDuque,CarmenzaUekusa,HidehiroHara,NoriyukiFujimoto,Yoshinorieng2011-05-16T00:00:00Zoai:scielo:S0103-50532011000500026Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2011-05-16T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
title |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
spellingShingle |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol Echigo,Shizue 24-ethyl-24-methylcholesterol 24-ethyl-24-methylcholesta-5,22-dien-3b-ol Topsentia ophiraphidites marine sterol orthoester Claisen rearrangement |
title_short |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
title_full |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
title_fullStr |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
title_full_unstemmed |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
title_sort |
C-24 stereochemistry of marine Sterols: (22E)-24-Ethyl-24-methylcholesta-5,22-dien-3b-oβl and 24-Ethyl-24-methylcholest-5-en-3β-ol |
author |
Echigo,Shizue |
author_facet |
Echigo,Shizue Castellanos,Leonardo Duque,Carmenza Uekusa,Hidehiro Hara,Noriyuki Fujimoto,Yoshinori |
author_role |
author |
author2 |
Castellanos,Leonardo Duque,Carmenza Uekusa,Hidehiro Hara,Noriyuki Fujimoto,Yoshinori |
author2_role |
author author author author author |
dc.contributor.author.fl_str_mv |
Echigo,Shizue Castellanos,Leonardo Duque,Carmenza Uekusa,Hidehiro Hara,Noriyuki Fujimoto,Yoshinori |
dc.subject.por.fl_str_mv |
24-ethyl-24-methylcholesterol 24-ethyl-24-methylcholesta-5,22-dien-3b-ol Topsentia ophiraphidites marine sterol orthoester Claisen rearrangement |
topic |
24-ethyl-24-methylcholesterol 24-ethyl-24-methylcholesta-5,22-dien-3b-ol Topsentia ophiraphidites marine sterol orthoester Claisen rearrangement |
description |
The C-24 configurations of (22E)-24-ethyl-24-methylcholesta-5,22-dien-3β-ol (1) and 24-ethyl-24-methylcholest-5-en-3β-ol (2), isolated from the Colombian Caribbean sponge Topsentia ophiraphidites, were determined to be R and S, respectively, by comparing their NMR data with those of stereodefined (24R)- and (24S)-samples that were synthesized in routes involving the orthoester Claisen rearrangement of Δ23-22-allylic alcohols. This is the first synthetic study where the Claisen rearrangement is used to introduce a C-24 quaternary center in a stereospecific manner with acceptable yield. X-ray analysis of 1 confirmed these stereochemical assignments. |
publishDate |
2011 |
dc.date.none.fl_str_mv |
2011-05-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532011000500026 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532011000500026 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-50532011000500026 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Journal of the Brazilian Chemical Society v.22 n.5 2011 reponame:Journal of the Brazilian Chemical Society (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Journal of the Brazilian Chemical Society (Online) |
collection |
Journal of the Brazilian Chemical Society (Online) |
repository.name.fl_str_mv |
Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
||office@jbcs.sbq.org.br |
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1750318172277309440 |