The LC-MS3 analysis of the peak at 8.2 min for kale water extract. (a) The compound at 8.2 min was purified and subjected to an HPLC analysis. (b) Full scan spectra (LC-MS) of the compound at 8.2 min as well as LC-MS2 and LC-MS3 spectra are shown. Arrowhead indicates unique ions shown by LC-MS, LC-MS2 and LC-MS3 analyses of KP3S7G. (c) The deduced chemical structure and fragment pattern of the compound at 8.2 min.