Synthesis of naturally occuring quinones. Part 20. Tandem Michael/Diels-Alder addition as a new strategy toward tetracyclic systems: synthesis of 11-deoxyanthracyclinones
Direct and regioselective reaction of 2,4-pentadienyltrimethylstannane with 3-acryloyl-5-methoxy-1,4-naphthoqinone afforded a tetracyclic compound, a key precursor for synthesizing 11-deoxyanthracycline antibiotics, by single step.