Menadione
Menadione, a vitamin. Synthetic naphthoquinone lacking the isoprenoid side chain. Serves as a circulating precursor for tissue menaquinone-4… Oral half-life 0.5 h.
Synthetic naphthoquinone lacking the isoprenoid side chain. Serves as a circulating precursor for tissue menaquinone-4 (MK-4): extrahepatic UBIAD1 prenyltransferase geranylgeranylates menadione to MK-4 in pancreas, testis, and brain. Menadione itself is redox-active and undergoes semiquinone cycling that can deplete glutathione and generate hydrogen peroxide — this is why synthetic K3 caused hemolytic anemia and kernicterus in neonates and was withdrawn from human OTC use (FDA ban 1963). Still used in animal feed and as a research tool.
Pharmacokinetics
- Oral — t½ 27 min · F 50%
Related compounds
Sources: PMID:24085302