IDENTIFICATION OF VITAMIN K1 (ALFALFA)

Abstract

OF VITAMIN K1 (ALFALFA)Degradation experiments which are being described elsewhere indicate quite clearly that vitamin K1 is 2-methyl-3-phytyl-1,4naphthoquinone, GIH~GOS This compound has been synthesized by Claisen's method for direct carbon alkylation from phytyl bromide and 1,4-dihydroxy-2-methylnaphthalene.Although the combustion analysis and the melting point of a mixture of the diacetate with an authentic specimen of diacetyldihydro vitamin K1 indicated the identity of the diacetates, it is deemed advisable to offer more convincing evidence of the synthesis.Chromic acid oxidation of the synthetic diacetate has given the same acid, 1,4diacetoxy-2-methylnaphthalene-3-acetic acid, that was obtained from the diacetate of the natural vitamin.Analysis, found, C 64.52, H 5.26; calculated for CI~H~BO~, C 64.55, H 5.10.The acid from the synthetic compound melted at 209-210'; from the diacetate of the natural compound, 209-210'; the mixed melting point showed no depression.The isolation of this acid from the oxidation products clearly indicates that the nuclear structure, the positions of the substituents, and the location of the ethylenic double bond are the same in both the natural and synthetic compounds.The bioassay of the diacetyldihydro derivatives of natural and synthetic vitamin K1 gave identical results.The potency of each was 660 units per mg.