Synthèse partielle de la (20 S )‐ψ‐vincamine et de la (20 S )‐épi‐16ψ‐vincamine

Partial Synthesis of (20 S )‐ψ‐Vincamine and (20 S )‐ epi ‐16ψVincamine An attempt of classification of the indole alkaloids is presented; (20 S )‐ψ‐vincamine. (20 S )‐16‐épi‐ψ‐vincamine and (20 S )‐ψ‐apo‐vincamine have been prepared from catharanthine by partial synthesis.