3d image of menadione skeletal formula

menadione vitamin k3 naphthoquinone nutritional supplement animal feed k2 prenyltransferase vertebrate ubiad1 blood-brain barrier provitamin biological activity bioactive nutrient prescription drug food additive nutraceutica dietary vitamin hypoprothrombinemia animal substance matter material compound component agent stuff reagent functional group precursor synthesis reaction production building block molecule molecular formula skeletal structural structure geometry biology biochemistry biomolecule biochemical 3d