- Biogenetically inspired enantioselective approach to Indolo[2,3-a]- and benzo[a]quinolizidine alkaloids from a synthetic equivalent of secologanin.
Biogenetically inspired enantioselective approach to Indolo[2,3-a]- and benzo[a]quinolizidine alkaloids from a synthetic equivalent of secologanin.
Organic letters (2005-07-01)
Oriol Bassas, Núria Llor, Maria M M Santos, Rosa Griera, Elies Molins, Mercedes Amat, Joan Bosch
PMID15987144
ABSTRACT
[reaction: see text] Racemic oxodiester 1 undergoes stereoselective cyclocondensation with (S)-tryptophanol, (S)-(3,4-dimethoxyphenyl)alaninol, or the corresponding amino acids, in a process involving a tandem dynamic kinetic resolution/desymmetrization of diastereotopic groups, to give bicyclic lactams, which are cyclized to substituted indolo[2,3-a]- and benzo[a]quinolizidines.
MATERIALS