Absolute configuration reassignment of nectamazin A: Implications to related neolignans
dc.citation.issue | 123283 | pt_BR |
dc.citation.volume | 304 | pt_BR |
dc.contributor.author | Batista, Andrea Nastri de Luca | |
dc.contributor.author | Santos, Carlos Henrique Totini dos | |
dc.contributor.author | Albuquerque, Ana Carolina Ferreira de | |
dc.contributor.author | Santos Jr, Fernando Martins dos | |
dc.contributor.author | Garcez, Fernanda Rodrigues | |
dc.contributor.author | Batista Jr, João Marcos [UNIFESP] | |
dc.contributor.authorLattes | http://lattes.cnpq.br/4209224090500050 | pt_BR |
dc.date.accessioned | 2024-03-20T11:50:15Z | |
dc.date.available | 2024-03-20T11:50:15Z | |
dc.date.issued | 2023-08-21 | |
dc.description.abstract | The ability of nature to produce structurally complex molecules makes the determination of the absolute configu- ration of natural products a challenging task. Although extensive NMR analysis generally allows for the reliable assignment of relative configurations, the assignments of absolute stereochemistry are commonly performed by empirical comparisons of optical rotation (OR) and/or electronic circular dichroism (ECD) data obtained for related molecules. Such an approach, however, may lead to misassignments and consequent error propagations. Herein, we present the case of the bicyclo(3.2.1)octane neolignan named (+)-nectamazin A. This compound was first reported in 2009 from Nectandra amazonum Nees. (Lauraceae) and had its absolute configuration determined as 7R,8S,3′S,4′R,5′S by means of experimental ECD spectroscopy. Our chemical studies on Ocotea aciphylla (Lauraceae) led to the isolation of (+)-nectamazin A. The extensive analysis of OR, ECD, and vibrational CD data aided by quantum chemical cal- culations, however, indicated (+)-nectamazin A to have the 7S,8R,3′R,4′S,5′R absolute configuration, in conflict with the configuration reported in the literature. The cause of the original incorrect assignment of (+)-nectamazin A derives from the direct comparison of experimental OR and ECD data obtained for structurally related molecules with different chromophoric systems. As an alternative, VCD spectroscopy is presented as a more reliable and sensitive technique to stereochemical investigations of bicyclo(3.2.1)octane neolignans. | pt_BR |
dc.description.sponsorship | Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) | pt_BR |
dc.description.sponsorshipID | 2019/22319-5 | pt_BR |
dc.identifier.doi | https://doi.org/10.1016/j.saa.2023.123283 | pt_BR |
dc.identifier.uri | https://hdl.handle.net/11600/70868 | |
dc.language | eng | pt_BR |
dc.publisher | Elsevier | pt_BR |
dc.relation.ispartof | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | pt_BR |
dc.rights | info:eu-repo/semantics/restrictedAccess | pt_BR |
dc.subject | Circular dichroism | pt_BR |
dc.subject | VCD | pt_BR |
dc.subject | DFT | pt_BR |
dc.subject | Stereochemistry | pt_BR |
dc.subject | Lignans | pt_BR |
dc.subject | Ocotea aciphylla | pt_BR |
dc.subject | Lauraceae | pt_BR |
dc.title | Absolute configuration reassignment of nectamazin A: Implications to related neolignans | pt_BR |
dc.type | info:eu-repo/semantics/article | pt_BR |
unifesp.campus | Instituto de Ciência e Tecnologia (ICT) | pt_BR |
unifesp.departamento | Não se aplica | pt_BR |
unifesp.graduacao | Não se aplica | pt_BR |
unifesp.graduateProgram | Não se aplica | pt_BR |
unifesp.knowledgeArea | Outra | pt_BR |