In this paper we report a disulfide formation of thiols induced by epolactaene and itsderivatives. We previously reported the disulfide formation of N-acetylcysteine methyl ester by epolactaene in a 1:1 MeOH/0.5 M NaHCO3 aq solution. The present studies reveal that the disulfide formation proceeds under mild conditions such as in PBS at pH 7.3, suggesting that epolactaene may induce disulfide formation