Acetate → Maleate(2-)

Participants

Reaction Steps

Specifically, the procedure is as follows. First, vitamin E (II) is reacted with maleic anhydride (III) in the presence of an alkaline carbonate (sodium carbonate, potassium carbonate or the like) or an alkaline acetate (sodium acetate, potassium acetate or the like) in a nonpolar solvent such as acetone, acetonitrile or tetrahydrofuran (THF) for about 1 to 3 hours while heating to give mono-tocopheryl maleate (or fumarate) (IV) (which is a novel compound not found in publications so far). The compound (IV) thus produced may further be subjected to a condensation reaction with an amino acid (glycine, β-alanine, γ-aminobutyric acid, 5-aminovaleric acid, ε-aminocaproic acid, anthranilic acid, tranexamic acid, proline, one of their esters, aminoethylsulfonic acid, or aminoethylsulfinic acid) or an amine (serotonin) in a solvent such as chloroform or tetrahydrofuran in the presence of an organic amine (pyridine, triethylamine or the like) according to the mixed anhydride method using ethyl chloroformate or the like to give a corresponding acid amide (V) of mono-tocopheryl maleate (or fumarate) (IV). The compound (IV) or (V) then is subjected to an addition reaction with an SH compound (glutathione, γ-glutamylcysteine, cysteine, penicillamine, an ester thereof, or cysteamine), a component of the present compound, at room temperature for about 3 to 6 hours and then about 1 to 3 hours while warming to give the present compound (I). A reaction solvent for this may be water or a solvent miscible with water, e.g., alcohol, acetonitrile or dioxane, which preferably is used as a mixture with water.

Provenance & Evidence