6AN (6-Aminonicotinamide) is an antimetabolite used to inhibit the NADPH-producing pentose phosphate pathway (PPP) in many cellular systems, making them more susceptible to oxidative stress. 6-Aminonicotinamide is a competitive inhibitor of NADP+-dependent enzyme glucose-6-phosphate dehydrogenase (G6PD) with Ki of 0.46 μM.