抄録
A fat-soluble derivative of riboflavin, riboflavin-2', 3', 4', 5'-tetrabutyrate (B_2-But) was crystallized from methyl alcohol-water solvent system (19 : 5,v/v), and reddish-yellow, rhombic crystals were obtained. Melting point of this recrystallized sample was found at 147-148℃ which is a little higher than that previously reported. Infrared spectrum of this sample shows that 2', 3', 4', 5'-tetrahydroxyl groups of riboflavin disappeared completely and that newly formed ester linkage between alcoholic hydroxyl group and carboxyl group of butyric acid appeared. Spectroscopic properties of B_2-But in several solvents were studied, and the molar extinction coefficients were determined. It was also found that B_2-But dissolves in water at low concentration.
