Absolute Configurations and Stereochemical Inversion Mechanism of Epimeric Securinega Alkaloids from Flueggea suffruticosa.
Org Lett
; 22(9): 3673-3678, 2020 05 01.
Article
em En
| MEDLINE
| ID: mdl-32319780
ABSTRACT
Three pairs of Securinega alkaloid epimers with a piperidin-2-yl moiety (1-6) were isolated from Flueggea suffruticosa, and their structures including absolute configurations were definitely characterized. An interconvertible C-2' epimerization process within each pair of epimers was observed. The following comprehensive experimental and theoretical investigations demonstrated an unusual stereochemical inversion mechanism of an N-substituted carbon stereogenic center, which was evidenced to be a protic solvent mediated process involving a tandem 1,4-elimination/1,4-addition as the key step.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Euphorbiaceae
/
Alcaloides
/
Securinega
Idioma:
En
Revista:
Org Lett
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2020
Tipo de documento:
Article