Total Synthesis of Angucyclines, 12 Biomimetic-Type Synthesis of the Racemic Non-Aromatic Angucyclinones of the SF 2315 and SS 228Y Types

摘要

The biomimetic-type aldol reaction of the tricyclic (E)-configured precursors 6a/b gave the racemic nonaromatic angucycline derivatives 11-13 of the SF 2315 and SS 288Y types. Chelate controlled conditions in the cyclization of 6b led to the regioisomeric product 10.