Levistilide a

Acetonitrile (HPLC grade) was obtained from Fisher Corporation (Waltham, MA, USA). Adenosine-5-two sodium phosphate (C₁₀H₁₃N₅Na₂O₁₀P₂) was purchased from Sigma-Aldrich Co (St. Louis, MO, USA). Sodium ferulic acid was obtained from Shanghai Yuan Ye Biotechnology Co., Ltd. (Shanghai, China). Glacial acetic acid, dimethyl sulfoxide (DMSO), and three sodium citrate (two water) C₆H₅Na₃O₇·2(H₂O) were of analytical grade and acquired from Guangzhou Chemical Reagent Factory (Guangzhou, China). Sodium chloride injection (0.9%, W/V) was purchased from Sichuan Cologne Pharmaceutical Co., Ltd. (Chengdu, China). CR decoction pieces (Product Batch No. 180802731) were manufactured by Kangmei Pharmaceutical Co., Ltd. (Guangdong, China) and deposited in the traditional Chinese Medicine Laboratory of Puning Production Base of Kangmei Pharmaceutical. Standards of vanillin, ferulic acid, senkyunolide I, senkyunolide H, coniferyl ferulate, Z-ligustilide, butylphthalide, senkyunolide A, and levistilide A (purities ≥ 98% by HPLC) were purchased from Chengdu Pufei De Biotech Co., Ltd. (Chengdu, China). Japanese big-eared white rabbits, male, weighing about 2.5 kg, were provided by Chengdu Dashuo Biotechnology Co., Ltd. (Chengdu, China).

Acetonitrile (HPLC grade) was obtained from Fisher Corporation (Waltham, MA, USA). Glacial acetic acid was analytical grade and acquired from Guangzhou Chemical Reagent Factory (Guangzhou, China). Nitric acid 67% was MOS grade and purchased from Tianjin Kemiou Chemical Reagent Co., Ltd. (Tianjin, China). Standards of chlorogenic acid, caffeic acid, vanillin, ferulic acid, senkyunolide I, senkyunolide H, coniferyl ferulate, Z-ligustilide, butylphthalide, senkyunolide A, butylidenephthalide, neocnidilide, and levistilide A (purities ≥ 98% by HPLC) were purchased from Chengdu Pufei De Biotech Co., Ltd. (Chengdu, China). Calibration solutions of 1,000 mg·L⁻¹ of Na, Mg, K, Ca, Mn, Fe, Cu, and Zn were all purchased from Agilent Technologies Inc. (USA). Internal standard elements, consisting of 1,000 mg·L⁻¹ of ⁷³Ge, ¹¹⁵In, and ²⁰⁹Bi, were obtained from National Institute of Metrology (China). All experimental solutions were prepared with ultrapure water (18.2 MΩ·cm⁻¹), which was produced by a purification system (Milli-Q Gradient, Millipore, USA).