Cervimycin A–D: A Polyketide Glycoside Complex from a Cave Bacterium Can Defeat Vancomycin Resistance

Abstract Cervimycins A–D are novel polyketide glycosides with significant activity against multi‐drug‐resistant staphylococci and vancomycin‐resistant enterococci. They are produced by a strain of Streptomyces tendae , isolated from an ancient cave. The structures of the cervimycins were determined by performing extensive NMR and chemical degradation studies. All cervimycins have a common tetracyclic polyketide core that is substituted with unusual di‐ and tetrasaccharide chains, composed exclusively of trideoxysugars; however, they differ in the acetyl and carbamoyl ring substituent and in the highly unusual terminal methylmalonyl and dimethylmalonyl residues.