1290lc 6540 accurate mass q tof

All solvents and chemicals were purchased from commercial suppliers and were used without further purification unless otherwise stated. Column chromatography was conducted on silica gel (200–300 mesh) and thin layer chromatography (TCL) was performed using silica gel 60 F254 (Qingdao Ocean Chemicals, Qingdao, China). ¹H NMR and ¹³C NMR spectra were recorded on a Bruker Avance 300 MHz spectrometer. High resolution mass spectra (HRMS) were recorded on an Agilent 1290LC-6540 Accurate Mass Q-TOF by using electrospray ionization (ESI). Fluorescent spectra were measured by using TU-1901 (Beijing Purkinje General Instrument Co., Ltd.) and F-280 (Tianjin Gangdong Technology Co., Ltd.). The cytotoxicity assay measures the absorption wavelength at 490 nm by means of an enzyme labeling device (Synergy HT). Fluorescence imaging of HOCl in live HeLa cells was measured under an Olympus FV1000 confocal fluorescence microscope.

All materials for synthesis were commercially available without further purification. All solvents used were of analytical reagent grade and all aqueous solutions were prepared using pure water. The caffeic acid tablets were purchased from Dezhou Deyao Pharmaceutical Co., Ltd. The ¹H NMR spectra and ¹³C NMR spectra were recorded on a Bruker AM-600 spectrometer (Billerica, MA), and chemical shift (δ) were given in parts per million relative to tetramethylsilane (TMS). High-resolution mass spectrometry (HRMS) spectra were recorded on an Agilent 1290LC-6540 Accurate-Mass Q-TOF by using electrospray ionization (ESI). Chromatographic datas were recorded on a Waters high-performance liquid chromatograph (Waters Corporation, USA), and the separated compounds were collected using a SHIMADZU LC-20AR preparative liquid chromatograph (Shimadzu, Japan). Ultraviolet absorption datas were collected on a HITACHI U-2910 UV-Visible spectrophotometer (Hitachi, Japan). Fluorescence datas were collected on an RF5301PC Fluorescence Spectrophotometer (Shimadzu, Japan).