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It is almost insoluble in cold water, slightly soluble in petroleum ether, and more soluble in polar organic solvents. In alkaline solutions it produces a reddish-brown color. Vitamin K is a derivative of 1,4-naphthoquinone. It is a planar molecule with one aromatic ring fused to a quinone subunit. [2] It is an isomer of 1,2-naphthoquinone.
Menadiol is an organic compound with the formula C 6 H 4 (COH) 2 (CH)(CH 3). It is formally a derivative of p-hydroquinone. The name vitamin K 4 can refer to: specifically this compound, [1] [2] its various esters, e.g. menadiol diacetate (acetomenaphthone), [3] [4] menadiol dibutyrate, [4] menadiol dimalonate, or [2] its various salts, like
Menadione is a synthetic [3] [4] organic compound with the formula C 6 H 4 (CO) 2 C 2 H(CH 3). It is an analog of 1,4-naphthoquinone with a methyl group in the 2-position. [5] It is sometimes called vitamin K 3. Use is allowed as a nutritional supplement in animal feed because of its vitamin K activity.
Vitamin K is a family of structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. [1] The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulation ("K" from Danish koagulation, for "coagulation") or for controlling binding of calcium in bones and other tissues. [2]
Vitamin K is a fat-soluble vitamin that is stable in air and moisture but decomposes in sunlight. [17] K 1 is a polycyclic aromatic ketone, based on 2-methyl-1,4-naphthoquinone, with a 3-phytyl substituent.
[2] [3] The most familiar type of animal sterol is cholesterol, which is vital to the structure of the cell membrane, and functions as a precursor to fat-soluble vitamins and steroid hormones. While technically alcohols, sterols are classified by biochemists as lipids ( fats in the broader sense of the term).
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
The conversion is not dependent on gut bacteria, occurring in germ-free rats [3] [4] and in parenterally-administered K 1 in rats. [5] [6] Tissues that accumulate high amounts of MK-4 have a capacity to convert up to 90% of the available K 1 into MK-4. [3] [4] [dubious – discuss] K 1 is converted to MK-4 in three steps: [7]