Abstract: Successive Rearrangements in Mass Spectra of Noncyclic PolyethersGuan Jingqu; Zou Zhichen; Bing Jiansheng; Yan Qingbin(Chemistry Department, Shandong Teachers' University,Jinan, 250014, China)Abstract: The mass spectra of ureide-type noncyclic polyethers with 2(3H)-benzoxazolone as end groups were studies. These compounds exhibited similiar mass spectra properties.McLafferty rearrangements occourded in M＋1 ion to give the fragment ion(m/z 207)which took further McLafferty rearrangements to give the fragment ions (177). Moreover,the fragment ion (m/z 177)took a new methyl rearrangement.Keywords: noncyclic polyether; mass spectra; McLafferty rearrangement; methyl rearrangement