Identification and characterization of chlorogenic acids, chlorogenic acid glycosides and flavonoids from Lonicera henryi L. (Caprifoliaceae) leaves by LC–MSn

We have developed the LC–MSn and LC–HRMS methods for the identification and characterization of chlorogenic acid glycosides from Lonicera henryi L. (Caprifoliaceae) leaves. •The phenolics of Lonicera henryi L. (Caprifoliaceae) leaves were investigated qualitatively by LC–MSn.•Thirteen chlorogenic acid glycosides were detected for the first time in nature.•The regiochemistry of chlorogenic acid glycosides was assigned based on the tandem mass spectra. The chlorogenic acids, chlorogenic acid glycosides and flavonoids of the leaves of Lonicera henryi L. (Caprifoliaceae) were investigated qualitatively by liquid chromatography tandem mass spectrometry. Thirty-one chlorogenic acids and their glycosides were detected and characterized to their regioisomeric level on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra. All of them were extracted for the first time from this source and thirteen of them were not reported previously in nature. For the positive identification of chlorogenic acid glycosides by LC–MSn, multiple reaction monitoring and targeted MSn experiments were performed. We have developed an LC–MSn method for the systematic identification of chlorogenic acid glycosides and were also able to discriminate between chlorogenic acids and their isobaric glycosides. It was also possible to discriminate between 5-O-(3′-O-caffeoyl glucosyl)quinic acid and 5-O-(4′-O-caffeoyl glucosyl)quinic acid by LC–MSn. This method can be applied for the rapid and positive identification of chlorogenic acids and their glycosides in plant materials, food and beverages.