2-Acetoxy-3-methoxy-5-methyl-p-benzoquinone (IV) was synthesized by two methods starting from vanillin but the yield was not good in either case. The hydroquinone compound of IV was condensed with phytol and the product was hydrolyzed to give 2-hydroxy-3-methoxy-5-methyl-6-phytyl-p-benzoquinone (XI). Treatment of XI with triethylamine afforded the chromenol compound (XII), and difference in color reaction with phosphomolybdic acid of demethylubichromenol (35)(C) derived from demethylubiquinone (B) gave a powerful support to the structure of the latter (B).