5,6-Dihydropyridin-2(1H)-one is a natural product from Piper longum.

N-Acetyl-L-glutamic acid (NAcGlu) is an acetylated amino acid. NAcGlu is biosynthesized from glutamic acid and acetyl-CoA by the enzyme N-acetyl glutamate synthase (NAGS).

Tyroserleutide TFA, isolated from the degradation products of porcine spleen, is a small molecular tripeptide which inhibits tumor growth both in vitro and in vivo.