Isolation and structural characterization of two large families of organosulfur compounds spontaneously formed upon cutting of onion (Allium cepa) were carried out. The structures of these hitherto unknown species, trivially named cepathiolactols and cepathiolactones, were established based on NMR, MS, and IR data. It was found that cepathiolactols (C_xH_yOS₃ and C_xH_yO₂S₄; x = 7–12, y = 14–24) are 3,4-dimethyl-γ-thiolactols bearing various side chains linked via a disulfanyl moiety at position C-5. On the other hand, cepathiolactones were shown to be 3,4-dimethyl-γ-thiolactones structurally analogous to cepathiolactols. Sensory properties of cepathiolactols were also evaluated, along with testing their ability to participate in the formation of pink discoloration of processed onion.

中文翻译：

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Cepathiolactols 和 Cepathiolactones – 在切洋葱中形成的两个新发现的有机硫化合物家族


对洋葱 （Allium cepa） 切开后自发形成的两大类有机硫化合物进行了分离和结构表征。这些迄今为止未知的物种（通常被命名为头孢内酯和头孢内酯）的结构是根据 NMR、MS 和 IR 数据建立的。研究发现，鲸蜡内酯（C_xH_yOS₃ 和 C_xH_yO₂S₄;x = 7–12， y = 14–24）是 3,4-二甲基-γ-硫代内酯，带有各种侧链，通过位置 C-5 的二硫烷基部分连接。另一方面，头孢内酯被证明是 3,4-二甲基-γ-硫内酯，结构类似于头孢内酯。还评估了 cepathiolactol 的感官特性，并测试了它们参与加工洋葱粉红色变色形成的能力。