Process for synthesis of boric acid ester
AssigneeEisai Co., Ltd.
InventorsShizumasa Kijima, Isao Yamatu, Kimio Hamamura, Norio Minami, Youji Yamagishi, Yuichi Inai
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Abstract
2,3-DIMETHOXY-5-METHYL-6-SUBSTITUTED-1,4-BENZOQUINONE HAVING THE FORMULA: ##STR1## in which S is an integer of 0 to 11 and A and B stand for hydrogen or may form a direct bond, Is prepared by reacting boric acid ester of 2,3-dimethoxy-5-methyl-1,4-benzohydroquinone with prenol or isoprenol having the above group R and subsequently reacting the resulting borate with a mild oxidant. The compound is useful as coenzyme Q and has various clinical effects.
Claims14
A process for synthesizing boric acid ester of 2,3-dimethoxy-5-methyl-6-substituted-1,4-benzohydroquinone, wherein the substituent at the 6 position is ##STR10## wherein R is as defined below, which comprises reacting (A) boric acid ester of 2,3-dimethoxy-5-methyl-1,4-benzohydroquinone prepared by reacting 2,3-dimethoxy-5-methyl-1,4-benzohydroquinone with a substance selected from the group consisting of orthoboric acid, boron oxide, metaboric acid and borax, with (B) a prenol having the formula ##STR11## or an isoprenol having the formula ##STR12## wherein R is ##STR13## in which s is an integer of from zero to 11, and A and B are hydrogens or A--B form a direct bond
- or a reactive derivative of said prenol or said isoprenol selected from the group consisting of lower alkyl ethers, esters and halides.
Dependencies are inferred from the claim text.