Ethyl acetate etoac

Glycidol, triethylamine (NEt₃), tetrabutylammonium hydrogensulfate (TBAHSO₄), phosphazene base t-BuP₄ solution (0.8 M in hexane), anhydrous toluene, and anhydrous benzyl alcohol were purchased from Sigma-Aldrich. Epichlorohydrin (ECH), 3,5-dimethoxyphenol trityl chloride, 4-phenyl phenol, (s)-trityl glycidyl ether ((s)-TGE), and 4-methoxyphenyl glycidyl ether (MPG) were obtained from Tokyo Chemical Industry. Moreover, 4-dimethylaminopyridine (DMAP) was purchased from Alfa Aesar. Potassium hydroxide (KOH) flakes and ethyl acetate (EtOAc) were obtained from Daejung. Anhydrous magnesium sulfate (MgSO₄) was purchased from Duksan. Furthermore, (s)-TGE and MPG were purified via azeotropic distillation using toluene cosolvent to remove moisture prior to polymerization. All other reagents were used as received without further purification. The deuterated NMR solvents CDCl₃ and CD₂Cl₂ were purchased from Cambridge Isotope Laboratory.

All plant samples were collected from Goesan-gun (Chungcheongbuk-do, Republic of Korea) in 2015 and were immediately cleaned, ground, lyophilized, and stored at −20 °C before use. Lipase from porcine pancreas type II, 4-methylumbelliferyl oleate (4-MUO), and quercetin (≥95%) was purchased from Sigma-Aldrich Co. (St. Louis, MO, USA). Kaempferol (≥98.3%), myricitrin (≥98.3%), quercitrin (≥98.5%), and avicularin (≥99.3%) were purchased from ChemFaces Biochemical Co. (Wuhan, Hubei, China), and their purity was confirmed analytically by proton nuclear magnetic resonance (¹H-NMR) and HPLC. Methanol, n-hexane, and ethyl acetate (EtOAc) were purchased from Daejung Chemicals & Metals Co. (Siheung-si, Gyeonggi-do, Republic of Korea), and were of analytical grade. Water and acetonitrile purchased from J. T. Baker Co. (Phillipsburg, NJ, USA) were of high-performance liquid chromatography (HPLC) grade. The acetonitrile was dehydrated by molecular sieves 4 Å (Sigma-Aldrich Co.) and filtered through a membrane filter (0.45 µm) before use. All of the other chemicals were of extra-pure grade.

¹H NMR data were recorded at 600 MHz on a Bruker Avance Neo 600 (Brucker, Billerica, MA, USA) spectrometer in the Central Laboratory of Kangwon National University (Chuncheon, Korea). The Mass experiements were performed on a Waters Xevo G2 qTOF mass spectrometer (Waters MS Technologies, Manchester, UK) with the UPLC system through an electrospray ionization (ESI) interface for the MN study, as well as the exact mass analysis. Silica gel Kieselgel 60 (40–60 μm, 230–400 mesh, Art. 9385, Merck, Darmstadt, Land Hessen, Germany) and Diaion HP-20 (Mitsubishi Chemical Industries Ltd., Chiyoda-ku, Tokyo, Japan) were used for column chromatography. Thin layer chromatography (TLC) was performed to monitor the different fractions of T. asiaticum using a Kieselgel 60 F₂₅₄ (Art. 5715, Merck, Darmstadt, land Hessen, Germany) and an RP-C₁₈ F₂₅₄ (Art. 15389, Merck, Darmstadt, Land Hessen, Germany). Semipreparative HPLC was performed on an Agilent 1260 Infinity Quaternary LC (Agilent, Santa, CA, USA) with an Inspire^TM 5 μm C₁₈ (250 × 21.2 mm, Dikima, Foothill Ranch, CA, USA). Methanol (MeOH), n-hexane, ethyl acetate (EtOAc) and n-butanol (n-BuOH) were purchased from Daejung (Si-heung, Korea). The other reagents were purchased from Sigma-Aldrich (St. Louis, MO, USA).