2746 Menadione Menadione is a synthetic naphthoquinone without the isoprenoid side chain and biological activity, but can be converted to active vitamin K2, menaquinone, after alkylation in vivo. 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 FDA because of their high toxicity. It is sometimes called vitamin K3, although derivatives of naphthoquinone without the sidechain in the 3-position cannot exert all the functions of the K vitamins. Menadione is a vitamin precursor of K2 which utilizes alkylation in the liver to yield menaquinones (MK-n, n=1-13; K2 vitamers), and hence, is better classified as a provitamin. 58-27-5 4055 C11H8O2 172.052430 White powder. 107°C 160 mg/L (at 30°C) Variable and ranges from 10% to 80% Menadione (vitamin K3) is involved as a cofactor in the posttranslational gamma-carboxylation of glutamic acid residues of certain proteins in the body. These proteins include the vitamin K-dependent coagulation factors II (prothrombin), VII (proconvertin), IX (Christmas factor), X (Stuart factor), protein C, protein S, protein Zv and a growth-arrest-specific factor (Gas6). In contrast to the other vitamin K-dependent proteins in the blood coagulation cascade, protein C and protein S serve anticoagulant roles. The two vitamin K-dependent proteins found in bone are osteocalcin, also known as bone G1a (gamma-carboxyglutamate) protein or BGP, and the matrix G1a protein or MGP. Gamma-carboxylation is catalyzed by the vitamin K-dependent gamma-carboxylases. The reduced form of vitamin K, vitamin K hydroquinone, is the actual cofactor for the gamma-carboxylases. Proteins containing gamma-carboxyglutamate are called G1a proteins. Hepatic 3, not classifiable as to its carcinogenicity to humans. (L135) The primary known function of vitamin K is to assist in the normal clotting of blood, but it may also play a role in normal bone calcification. Menadione (vitamin K3), which is not used as a nutritional supplemental form of vitamin K for humans, has been reported to cause adverse reactions, including hemolytic anemia. Large doses have also been reported to cause brain damage. 2009-07-21T20:26:13Z 2026-05-14T16:24:26Z Menadione C05377 109135 112260 113811 115430 118650 122700 137167 138140 154870 176860 176880 176930 188055 192090 204690 214900 215100 219700 227220 227500 227600 245150 252650 261515 277450 302960 305900 306900 310400 600424 600441 600646 601841 602421 602497 604428 604429 604824 605271 607473 607542 607748 608547 608838 610842 28869 CPD-3766 Menadione DB00170 VK3 true CC1=CC(=O)C2=CC=CC=C2C1=O C11H8O2 InChI=1S/C11H8O2/c1-7-6-10(12)8-4-2-3-5-9(8)11(7)13/h2-6H,1H3 MJVAVZPDRWSRRC-UHFFFAOYSA-N 172.18 172.0524295 Exogenous Solid 2.2 HMDB01892 CHEMBL590 3915 <p>Joachim U. Schneider, Hans Kiefer, &#8220;Menadione choline bisulfite adduct, its preparation and antihemorrhagic compositions.&#8221; U.S. Patent US4735969, issued January, 1980.</p> CHEM002136 DTXSID4021715 NS00010106 2-methyl-1,4-dihydronaphthalene-1,4-dione 34.14 50.5403 17.637158614910383 0 2 0 12.936644003276722 -7.157932075900291 0 2 1.91 -2.53 5.04e-01 g/l