The 1-(1- and 2-naphthoyl)-3-n-pentylindole shows only two fragment ions at m/z 155 and the m/z 127. The JWH-018 shows one unique major fragment ion at m/z …show more content…
The six target compounds are subdivided into three groups based on their base peaks in the EI- mass spectra, each group have two compounds. First group shows the m/z 200 as the base peak including 2,3- and 2,5-dimethoxybenzoyl isomers. Second group shows the m/z 334 ion as the base peak including 2,4- and 2,6-dimethoxybenzoyl isomers. Third group shows the m/z 351 ion as the base peak for the 3,4- and 3,5-dimethoxybenzoyl isomers. The ortho-dimethoxy substituted isomers show unique fragment ions occurring at m/z 334 and m/z 200. Possible mechanism for the m/z 200 fragment ion is proposed and supportive analytical studies were carried out in this