Cytosporone E: racemic synthesis and preliminary antibacterial testing.

The antibiotic cytosporone E (isolated from the broth of the endophytic fungi CR 200 (Cytospora sp.) and CR 146 (Diaporthe sp.)) was synthesized as a racemic mixture. The key step in the synthesis is the Meyers ortho-alkylation of a chiral aromatic oxazoline. Preliminary antibiotic activity shows antibiosis against Gram-positive bacteria but not Gram-negative bacteria as previously reported.