Menadione
IUPAC name	2-methylnaphthalene-1,4-dione
Identifiers
CAS number	58-27-5 Y
PubChem	4055
SMILES	CC1=CC(=O)C2=CC=CC=C2C1=O
Properties
Molecular formula	C11H8O2
Molar mass	172.18
Melting point	102 °C
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Menadione is a polycyclic aromatic ketone, based on 1,4-naphthoquinone,^[1] with a 2-methyl substituent.

Contents 1 Terminology 2 Uses 3 See also 4 References

[edit] Terminology

It is sometimes called vitamin K₃,^[2] although derivatives of naphthoquinone without the side chain in the 3-position cannot exert all the functions of the K vitamins. Menadione is a vitamin precursor of K₂ which utilizes alkylation to yield menaquinones (MK-n, n=1-13; K₂ vitamers), and hence, is better classified as a provitamin.

It is also known as "menaphthone".^[3]

[edit] Uses

Despite the fact that it can serve as a precursor to various types of vitamin K, menadione is generally not used as a nutritional supplement. Large doses of menadione have been reported to cause adverse outcomes including hemolytic anemia due to G6PD deficiency, neonatal brain or liver damage, or neonatal death in some cases. Moreover, menadione supplements have been banned by the U.S. Food and Drug Administration (FDA) because of their high toxicity. Menadione has been used experimentally as a chemotherapic agent for cancer, ca 1945, but has lost ground to much safer, human form, vitamin K₂ vitamers. Low level menadione is still used as an inexpensive micronutrient for livestock in many countries. Forms of Menadione are also included in some pet foods as a source of vitamin K.

Lately, menadione has been mentioned again as a treatment for cancer in conjunction with vitamin C (See "The end of cancer" by April Kirkendoll) but modern researchers and trials are investigating nontoxic K₂ vitamers such as menaquinone-4^[4] in conjunction with more comprehensive regimens.

[edit] See also

• Vitamin K

[edit] References

v • d • e Vitamins (A11) Fat soluble A Retinol · β-Carotene · Tretinoin · α-Carotene D D2 (Ergosterol, Ergocalciferol)  · D3 (7-Dehydrocholesterol, Previtamin D3, Cholecalciferol, 25-hydroxycholecalciferol, Calcitriol (1,25-dihydroxycholecalciferol), Calcitroic acid) D4 (Dihydroergocalciferol)  · D5  · D analogues (Dihydrotachysterol, Calcipotriol, Tacalcitol, Paricalcitol) E Tocopherol (Alpha, Beta, Gamma, Delta) · Tocotrienol · Tocofersolan K Naphthoquinone · Phylloquinone/K1 · Menatetrenone/K2 · Menadione/K3 Water soluble B B1 (Thiamine) · B2 (Riboflavin) · B3 (Niacin, Nicotinamide) · B5 (Pantothenic acid, Dexpanthenol, Pantethine) · B6 (Pyridoxine, Pyridoxal phosphate, Pyridoxamine) B7 (Biotin) · B9 (Folic acid, Dihydrofolic acid, Folinic acid) · B12 (Cyanocobalamin, Hydroxocobalamin, Methylcobalamin, Cobamamide)  · Choline C Ascorbic acid  · Dehydroascorbic acid see also: enzyme cofactors, enzymes, Multivitamins

v • d • e Antihemorrhagics (B02) Hemostatics (coagulation) Systemic Vitamin K Phytomenadione/K1 · Menadione/K3 Coagulation factors intrinsic: IX/Nonacog alfa · VIII extrinsic: VII/Eptacog alfa common: X · II/Thrombin · I/Fibrinogen Other systemic Etamsylate · Carbazochrome · Batroxobin · thrombopoietin receptor agonist (Romiplostim, Eltrombopag) Local Absorbable gelatin sponge · Oxidized cellulose · Tetragalacturonic acid hydroxymethylester · Thrombin · Collagen · Calcium alginate · Epinephrine/Adrenalone Antifibrinolytics amino acids (Aminocaproic acid, Tranexamic acid, Aminomethylbenzoic acid) serpins (Aprotinin, Alfa1 antitrypsin, C1-inhibitor, Camostat)