Macrolides are a relatively common structural motif prevalent in Nature. However, the structures of these large ring lactones have been relatively difficult to elucidate via NMR spectroscopy due to the minute amounts of compounds that are sometimes obtainable from natural sources. Thus, GC-MS analysis of individual macrolactones has become the method of choice for the structural identification of these compounds. Here we discuss the mass spectrometric behavior of aliphatic macrolides, evaluating spectra from numerous compounds of various ring size, including derivatives containing methyl branches as well as double bonds. The specific fragmentation of these macrolactones under electron impact conditions allows for the development of a general rule set aimed at the identification of similar compounds by mass spectrometry. In addition, the mass spectra of dimethyl disulfide adducts of unsaturated macrolides are discussed. The mass spectra of almost 50 macrolides are presented.

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脂肪族大环内酯类，重要的化学信息素或信息素的质谱分析

大环内酯类是自然界中相对普遍的结构基序。然而，由于有时可从天然来源获得的微量化合物，通过NMR光谱法难以阐明这些大环内酯的结构。因此，单个大内酯的GC-MS分析已成为这些化合物结构鉴定的首选方法。在这里，我们讨论脂族大环内酯的质谱行为，评估来自各种环尺寸的许多化合物的光谱，包括含有甲基分支和双键的衍生物。这些大内酯在电子轰击条件下的特定断裂，允许开发通用规则集，该通用规则集旨在通过质谱法鉴定相似的化合物。此外，讨论了不饱和大环内酯的二甲基二硫加合物的质谱。给出了近50种大环内酯类化合物的质谱图。