A 80915A is A semi-naphthoquinone antibiotic from Streptomyces aculeolatus. It is a potent inhibitor of gastric (H(+)-K+)-ATPase. Inhibition by A80915A is dependent on the conformation of gastric (H(+)-K+)-ATPase, potassium slows the rate of inhibition by
AK-135 is a derivative of 1,4-naphthoquinone (Menadione). AK-135 has been shown to restore the electron flow in defective respiratory chain (hypoxia or rotenone) systems more effectively than Menadione.