Lactonamycin, a New Antimicrobial Antibiotic Produced by Streptomyces rishiriensis.

Studies on the Total Synthesis of Lactonamycin: Synthesis of the Fused Pentacyclic B–F Ring Unit

“…Biological evaluation of lactonamycin (1) against Gram-positive bacteria showed significant levels of antimicrobial activity. [3] Remarkably, it was especially active against clinically isolated methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). In addition, lactonamycin (1) showed significant levels of cytotoxicity against various tumor cell lines.…”

“…Lactonamycin (1) [1] and the more recently isolated lactonamycin-Z (2) [2] possess unique structural architectures and intriguing biological activities. The novel, highly functionalized hexacyclic aglycon core, known as lactonamycinone (3), contains, in the western half, a highly oxygenated fused perhydrofuranfuranone ring functionalized by a labile tertiary methoxy group, and in the eastern half, a naphtha[e]isoindole ring system.…”

“…In addition, lactonamycin (1) showed significant levels of cytotoxicity against various tumor cell lines. [3] The interesting biological properties combined with the challenging structure of lactonamycin (1) have generated considerable interest in the total synthesis of this complex and fascinating molecule. So far, six groups have reported synthetic studies directed towards the total synthesis of lactonamycin (1).…”

“…[3] The interesting biological properties combined with the challenging structure of lactonamycin (1) have generated considerable interest in the total synthesis of this complex and fascinating molecule. So far, six groups have reported synthetic studies directed towards the total synthesis of lactonamycin (1). Danishefsky and Cox were the first to report two routes towards the construction of the model ABCD ring system by using an oxidative dearomatization reaction [4] and a diastereoselective dihydroxylation reaction.…”

The chemistry of isoindole natural products

“…Anthraquinone-type alkaloids: Lactonamycin ( 215 ) and lactonamycin Z ( 217 ) were isolated from Streptomyc es rishiriensis and Streptomyces anglieri in 1996 and 2003 [157–158]. Both compounds are potent antibacterial agents against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) [159].…”