Synthesis of the nontryptamine moiety of the Aspidosperma-type indole alkaloids via cleavage of a cyclic .alpha.-diketone monothioketal. An efficient synthesis of (.+-.)-quebrachamine and a formal synthesis of (.+-.)-tabersonine
Synthesis of the nontryptamine moiety of the Aspidosperma-type indole alkaloids via cleavage of a cyclic .alpha.-diketone monothioketal. An efficient synthesis of (.+-.)-quebrachamine and a formal synthesis of (.+-.)-tabersonine