Isoacteoside

Caffeic acid (purity ≥98%), salidroside (purity ≥98%) and acteoside (purity ≥98%) were purchased from Aladdin (Shanghai, China). Tyrosol (purity ≥98%) and isoacteoside (purity ≥98%) were purchased from Yuanye Biotechnology Co. (Shanghai, China). CoCl₂ was purchased from Sigma-Aldrich (St. Louis, MO, USA). HPLC-grade acetonitrile and guaranteed-grade formic acid were obtained from Merck (Shanghai, China). Other chemicals and reagents (analytical grade) were purchased from Sinopharm Chemical Regent Co. (Shanghai, China).

The standard substance such as acteoside, isoacteoside, echinacoside, cistanoside A, and 2′- acetylacteoside were purchased from Shanghai Yuanye Biotechnology Co. Ltd (Shanghai, China). Cistanoside F, cistanoside C, osmanthuside B, and tubuloside B were purchased from Chengdu Pfeide Biotechnology Co. Ltd (Chengdu, China). The purity of all standards was no less than 98%. HPLC grade methanol and acetonitrile was purchased from Aladdin Chemistry Inc. (Shanghai, China). Deionized water was obtained using a MilliQ50 SP Reagent Water System (Bedford, MA, USA) for preparing samples and mobile solution. All other organic solvents used in this study were of analytical grade and purchased from Shanghai Chemical Co. Ltd (Shanghai, China).