386301.fig.002a
(a)
386301.fig.002b
(b)
386301.fig.002c
(c)
386301.fig.002d
(d)
386301.fig.002e
(e)
386301.fig.002f
(f)
Figure 2: (a) ESI mass spectrum of compound 3d [M + H]+ ion (m/z 442.10). (b) MS2 spectrum of m/z 442.10. (c) In-source fragmentation of compound 3d. (d) MS2 spectrum of m/z 374.10. (e) MS2 spectrum of m/z 271.10. (f) MS2 spectrum of m/z 214.20.