1957 年 5 巻 3 号 p. 272-276
Of the 17 kinds of unknown cardiotonic glycoside-like substance contained in the seeds of Digitalis purpurea, described in Part II of this series, a glycoside corresponding to substance C-I was isolated. This substance had a bitter taste and came as needle crystals of m. p. 194∼197°(Kofler, uncorr.) ; [α]21D+1.9±2° ; C35H54O13·2H2O ; negative to Keller-Kiliani reaction, giving brown sulfuric acid layer, and positive to Legal and Raymond reactions ; U.V. λEtOHmax 217mμ (log ε 4.23). These results indicated the substance to be a cardiotonic glycoside. Hydrolysis by the Mannich method afforded β-anhydrodigitoxigenin and digitoxigenin, and the sugar portion was identified as fucose and glucose by paper chromatography. Determination of glucose by the Borel-Hostettler-Deuel method, as in the case of gitostin, indicated the presence of 1 mole. Confirming this substance to be diglycoside, a new cardiotonic glycoside of digitoxigenin series, it was named glucodigifucoside.