Vitamin K2, also known as menaquinone, is a fat-soluble vitamin that plays a crucial role in blood clotting and bone health. It exists in several different forms, with the most common forms being menaquinone-4 (MK-4) and menaquinone-7 (MK-7). These different forms of vitamin K2 have slightly different chemical structures and physical properties.
Chemical Structure:
The chemical structure of vitamin K2 consists of a naphthoquinone ring with a side chain. The number and arrangement of isoprenoid units in the side chain vary among the different forms of vitamin K2. Here are the structures of MK-4 and MK-7:
1.Menaquinone-4 (MK-4):
MK-4 has a side chain composed of four isoprenoid units (4 repeats of the isoprene structure).
The chemical formula for MK-4 is C31H40O2.
The systematic name for MK-4 is 2-Methyl-3-[(2E,7R,11R)-3,7,11,15-tetramethylhexadeca-2,6,10,14-tetraen-1-yl]naphthalene-1,4-dione.
2.Menaquinone-7 (MK-7):
MK-7 has a longer side chain composed of seven isoprenoid units.
The chemical formula for MK-7 is C46H64O2.
The systematic name for MK-7 is 2-Methyl-3-[(2E,6E,10E,14E,18E,22E,26E,30E,34E,38E)-3,7,11,15,19,23,27,31,35,39-decamethyltetraconta-2,6,10,14,18,22,26,30,34,38-decaen-1-yl]naphthalene-1,4-dione.
Physical Properties:
Vitamin K2 is a fat-soluble vitamin, and its physical properties can vary slightly depending on the specific form (e.g., MK-4 or MK-7). Here are some general physical properties:
State: Vitamin K2 is a fat-soluble compound and is typically found as a yellow, oily substance.
Solubility: It is insoluble in water but soluble in fat (lipids).
Melting Point: The melting point may vary depending on the specific form, but it generally falls within the range of 32°C to 37°C (89.6°F to 98.6°F).
Boiling Point: Since vitamin K2 decomposes before reaching its boiling point, it does not have a well-defined boiling point.
Odor and Taste: Vitamin K2 does not have a distinct odor or taste.
It’s important to note that vitamin K2 is an essential nutrient for the body and plays a vital role in blood clotting and maintaining healthy bones. Different forms of vitamin K2 are found in various food sources, and they are also available as dietary supplements to support overall health.