Vitamin K -- info please

Pieter Proot pieter.proot at
Tue Mar 7 08:47:34 EST 1995

In article <3j53kb$kfg at>, tivol at wrote:

> In article <NEWTNews.4369.793676556.CROBBINSON@
>>, crobinson at writes:
> >[snip]
> >I am attempting to find out the function of vitamin K (on a molecular level)
> >in the body. [snip] I am also wondering as to how many type of Vitamin K
> >exist.
> >

History:  Vit K was discovered in 1929 by Dam.  He found that chickens on
a certain diet developped spontaneous bleedings, due to a low prothrombine
level in the blood.  Six years later he discovered that is was because of
a fatty product he then called Koagulations Vitamin (German): Vit K.

Two natural vit K products were discovered: Vit K1 (VK1) and Vit K2
(VK2).  First synthesis of VK1 was in 1939 by Fieser.  However, many
different chinonderivatives were discovered that had VK activity.

Structuree & properties:  VK is soluble in fatty solutions.  It is
available in many plant derived oils.  The product is light sensitive, but
it is rather resistant against heat.
VK1 and VK2 are naphtochinonderivatives (sorry: no structure can be send
this way, but they can easily be found in the Merck Index, centennial
edition).  Several synthetic derivatives are available, see table below:

VK1   Fyllochinon    2-methyl-3-fytyl-1,4-naphtochinon    from patatoes etc

VK2   Farnochinon    2-methyl-3-farnesyl-digeranyl-1,4-naphtochinon   (bacteria)

VK3   Menadion       2-methyl-1,4-naphtochinon           synthetic

VK4   Menadiol       2-methyl-1,4-naphtohydrochinon      synthetic

VK5                  4-amino-2-methylnaphtol                "

VK6                  2-methyl-1,4-diaminonaphtol            "

VK7                  4-amino-3-methylnaphtol                "

Since the natural products are not soluble in water, a bisulphite
derivative is used.

Biochemical role of the vitamine can easily be found in any textbook of
biochemistry and/or physiology.  Note that the vitamine has an important
role in  bloodcoagulation.

Hope this helps.

Pieter Proot, Pharm           e-mail: Pieter.Proot at

Katholieke Universiteit Leuven
Laboratory of PHYSIOLOGY,
O&N Gasthuisberg, Herestraat 49
B-3000 Leuven, BELGIUM
Tel: + 32 16 34 57 27                           Fax: + 32 16 34 59 91

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