Synthetic Studies of Kinamycin Antibiotics: Stereoselective Synthesis of the Highly Oxygenated D‐Ring and Construction of the ABD‐Ring System of Kinamycins

Abstract

A concise and stereoselective synthesis of the highly oxygenated D‐ring of the kinamycin family of antitumor antibiotics was achieved from commercially available 3‐methyl‐2‐cyclohexen‐1‐one. The key steps included a regioselective isomerization of a cis‐epoxy alcohol, a regioselective reductive ring opening of a benzylidene ketal, and a stereoselective α‐hydroxy‐directed ketone reduction. The Ullmann coupling between a bromonaphthaldehyde AB‐ring fragment and an α‐iodocyclohexenone, which is a versatile D‐ring precursor, effected the construction of the functionalized ABD‐ring system that may provide access to kinamycin F and its structural analogues.

Iron-Catalyzed Tandem Conia–Ene/Friedel–Crafts Reactions of o-Alkynyldihydrochalcones: Access to Benzo[b]fluorenes

“…Benzo­[ b ]­fluorenes are important polycyclic aromatic hydrocarbons (PAHs) that have potential applications in multiple fields. The benzo­[ b ]­fluorene core is featured in the kinamycin family of secondary metabolites, which possess significant antibiotic and cytotoxic activities . Certain benzo­[ b ]­fluorene derivatives have been proposed as nonsteroidal drug candidates for the estrogen receptor related medical treatments .…”