The structures of pentenomycins I and II, new antibiotics produced by Streptomyces eurythermus MCRL 0738, were proposed to be 4, 5-dihydroxy-5-hydroxymethyl-cyclopent-2-en-1-one and 5-hydroxy-5-hydroxymethyl-4-acetoxy-cyclopent-2-en-1-one respectively by chemical and spectroscopic methods.
