Armeniaspirol A is a major component of the complex produced by Streptomyces armeiacus, discovered by researchers at Sanofi in 2012. Armeniaspirols are a novel class of antibiotics with a unique chlorinated spiro[4.4]non-8-ene scaffold, potently active against Gram-positive pathogens including MRSA and VRE. Armeniaspirol A is a protonophore disrupting the membrane potential and decreases oxygen consumption in mitochondria. Armeniaspirol A inhibits the ATP-dependent proteases ClpXP and ClpYQ in vitro and in the model Gram-positive Bacillus subtilis. The pyrrole chloro group and the methyl group appear to be important for antimicrobial activities. Armeniaspirol A is also active against H. pylori.