Abstract: The Regular Patterns of Mass Spectrometry of Sterols and Related Derivatives (Ⅱ) Mass Spectrometric Fragmentation Typicality of △~5-, △~7-, △~8-, Steryl AcetatesZeng Zhi; Zeng Longmei(Department of Chemistry, Zhongshan University, Guangzhou 510275,China)Abstract: In the studies on the marine sterols isolated from the South China Sea sponges, we.summerized the fragmentation mechanism of the most important peaks of mass spectrometry of △~5-, △~7-, △~8-,-steryl acetates and the regular patterns of mass spectrometryof these sterol derivatives.Keywords: marine sterol; mass spectrum; fragment