Total synthesis of (−)-eudistomins with an oxathiazepine ring. Part 2. Synthesis of (−)-eudistomins C, E, F, K, and L

Eudistomins L, K, C, E (30) and F (33) were synthesized from the corresponding N-hydroxytryptamine 21 and the D-cysteinal 23. A bromine of eudistomin L was biomimetically introduced onto the pyrroloindolic intermediate 8. Other eudistomins were prepared from substituted indoles 17. A modified Pummerer reaction was used to obtain the oxathiazepine ring.