Total synthesis and structure of the ramoplanin A1 and A3 aglycons: two minor components of the ramoplanin complex.
Ramoplanin is a potent antibiotic, first disclosed in 1984, that acts by inhibiting bacterial cell-wall biosynthesis. The original ramoplanin complex was shown to consist of a mixture of three closely related compounds, ramoplanin A1-A3, of which ramoplanin A2 is the most abundant. The structure of ramoplanin A2 was unambiguously established first through a series of extensive spectroscopic studies, allowing complete stereochemical assignments and subsequently providing a minor reassignment of the side-chain double-bond stereochemistry and, most recently, through total synthesis of authentic material. Here we report the total syntheses of the aglycons of the minor components of the ramoplanin complex, A1 and A3, which unambiguously establish their structure and provide an expected structural revision for the lipid side-chain double-bond stereochemistry.
Shin
Dongwoo
D
Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Rew
Yosup
Y
Boger
Dale L
DL
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry*; D002625:Chemistry, Organic / Q000379:methods; D047630:Depsipeptides; D015394:Molecular Structure; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D000900:Anti-Bacterial Agents; D047630:Depsipeptides; D010456:Peptides, Cyclic; C041438:ramoplanin