Phylloquinone

"Phylloquinone is a polycyclic aromatic ketone, based on 2-methyl-1,4-naphthoquinone, with a 3-phytyl substituent."

"It is a fat-soluble vitamin that is stable to air and moisture but decomposes in sunlight. It is found naturally in a wide variety of green plants."

"It is often called vitamin K₁^[1], phytomenadione or phytonadione. Sometimes a distinction is made with phylloquinone considered natural and phytonadione considered synthetic."

"A stereoisomer of phylloquinone is called vitamin k₁ (note the difference in capitalization)."

"Phylloquinone is an electron acceptor during photosynthesis, forming part of the electron transport chain of Photosystem I."

"Its best-known function in animals is as a cofactor in the formation of coagulation factors II (prothrombin), VII, IX, and X by the liver. It is also required for the formation of anticoagulant factors protein C and S. It is commonly used to treat warfarin toxicity, and as an antidote for coumatetralyl."

"Vitamin K is also required for bone protein formation."