Azaserine is a naturally occurring serine derivative diazo compound with antineoplastic and antibiotic properties deriving from its action as a purinergic antagonist and structural similarity to glutamine.

Azaserine acts by competitively inhibiting glutamine amidotransferase, a key enzyme responsible for glutamine metabolism.

Azaserine inhibits the rate limiting step of the metabolic hexosamine pathway and irreversibly inhibits γ-glutamyltransferase by acting directly at the substrate-binding pocket.

Independent of hexosamine pathway inhibition, azaserine has been demonstrated to protect against hyperglycemic endothelial damage by elevating serum concentrations of manganese-superoxide dismutase, directly reducing the concentration of reactive oxygen species.

Azaserine also downregulates the expression of VCAM-1 and ICAM-1 in response to TNF-α, and research indicates that it may have potential in identifying the L-leucine-favoring system transporter in human T-lymphocytes.