Synthesis of the Cyanobacterial Antibiotics Anaephenes A and B

Abstract

The first syntheses of the antibacterial natural products anaephenes A (<b>1</b>) and B (<b>2</b>) are reported. Both natural products were synthesized in five linear steps from commercially available <i>tert</i>-butyl(3-iodophenoxy)dimethylsilane. Key steps for the synthesis included a Sonogashira cross-coupling and a Julia-Kocienski olefination to selectively construct the <i>E</i>-alkene present in the natural products. This synthetic route allowed the identities and antimicrobial activities of anaephenes A (<b>1</b>) and B (<b>2</b>) to be confirmed. Additionally, these compounds displayed antimicrobial activity against methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) with MIC values of 16 and 8 μg/mL, respectively.