Abstract
This paper describes synthesis and some properties of a mixed disulfide of lipoic acid and pantetheine. Pantetheine was prepared from pantethine by reduction with Na_2S, then reacted with 2 moles of DL-α-lipoic acid dissolved in a NaHCO_3 aqueous solution by being allowed to stand for 3 to 4 hours at pH 7.4 at room temperature. The reaction product showed the behaviors corresponding to the compound, which consisted of one mole of lipoic acid and one mole of pantetheine with KCN-nitroprusside test, thiol exchange reaction by cysteine treatment, bioautography using lipoic acid-requiring microorganisms (Stc. faecalis 10 C1 and Coryneb. bovis) and pantetheine-responding microorganisms (L. bulgaricus B-1 and L. arabinosus) as test organisms. Its ultraviolet and infrared absorption spectra were consistent with the structure proposed above. The growth effect of the mixed disulfide on lipoic acid-requiring microorganism, e. g. Stc. faecalis, was significantly greater than that of α-lipoic acid or a mixture of α-lipoic acid and pantethine.
