Thaxton-Weissenfluh Amber, Belal Tarek S, DeRuiter Jack, Smith Forrest, Abiedalla Younis, Neel Logan, Abdel-Hay Karim M, Clark C Randall
Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA.
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.
J Chromatogr Sci. 2018 Oct 1;56(9):779-788. doi: 10.1093/chromsci/bmy059.
The indole ring regioisomeric methoxy-1-n-pentyl-3-(1-naphthoyl)-indoles represent indole ring-substituted analogs of the synthetic cannabinoid JWH-018. The electron ionization mass spectra show equivalent regioisomeric major fragments resulting from cleavage of the groups attached to the central indole nucleus. The characteristic (M-17)+ fragment ion at m/z 354 resulting from the loss of OH group is significant in the mass spectra of all four compounds. Fragmentation of the naphthoyl and/or pentyl groups yields the cations at m/z 314, 300, 244 and 216. The vapor-phase infrared spectra provide a number of characteristic absorption bands to identify the individual isomers. Gas chromatographic separations on a capillary column containing a film of trifluoropropylmethyl polysiloxane (Rtx-200) provided excellent resolution of these compounds, their precursor indoles and intermediate pentylindoles. The elution order appears related to the degree of crowding of indole ring substituents.
吲哚环区域异构的甲氧基 - 1 - 正戊基 - 3 -（1 - 萘甲酰基） - 吲哚代表合成大麻素JWH - 018的吲哚环取代类似物。电子电离质谱显示，由于连接在中心吲哚核上的基团断裂而产生等效的区域异构主要碎片。在所有四种化合物的质谱中，因失去OH基团而在m/z 354处出现的特征性（M - 17）+碎片离子很显著。萘甲酰基和/或戊基的裂解产生m/z 314、300、244和216处的阳离子。气相红外光谱提供了许多特征吸收带以识别各个异构体。在含有三氟丙基甲基聚硅氧烷薄膜（Rtx - 200）的毛细管柱上进行气相色谱分离，可对这些化合物、其前体吲哚和中间戊基吲哚进行出色的分离。洗脱顺序似乎与吲哚环取代基的拥挤程度有关。
