Exactive orbitrap plus spectrometer

Melting points were determined on a Kofler Thermogerate apparatus and were uncorrected. Infrared spectra were recorded on a JASCO FT/IR-400 spectrophotometer. Nuclear magnetic resonance spectra were recorded, unless otherwise specified, on a Bruker AM-400 instrument using deuterated chloroform or dimethylsulfoxide solutions containing tetramethylsilane as an internal standard. ESI/MS experiment was carried out on an UHPLC Eksigent1 coupled with MS detector ABSciex1, Triple Quad 4500 model equipment. HRMS-ESI-MS experiments were performed using a Thermo Scientific Exactive Plus Orbitrap spectrometer with a constant nebuliser temperature of 250 °C. The experiments were carried out in positive or negative ion mode, with a scan range of m/z 300.00–1510.40 and a resolution of 140,000. The samples were infused directly into the ESI source via a syringe pump at flow rates of 5 µL·min⁻¹ through the instrument’s injection valve. Thin layer chromatography (TLC) was performed using Merck GF-254 type 60 silica gel. Column chromatography was carried out using Merck type 9385 silica gel. The purity of the compounds was determined by TLC and high-resolution mass spectrometry (HRMS) and for 4s by HLPC (Figure S8).

¹H and ¹³C NMR spectra were recorded on a Bruker Avance 500 MHz spectrometer at 300 K. Coupling constants in Hz were measured from-one dimensional spectra. HRMS-ESI analyses were carried out using a Thermo Scientific Exactive Plus Orbitrap spectrometer with a constant nebulizer temperature of 250°C. The experiment was carried out in positive ion mode at high resolution (resolving power: 140,000 (full width half-maximum peak width at m/z 300, R_fwhm). The samples were infused directly into the ESI source using a syringe pump at flow rates of 5 μL min^-1. All chemicals were reagent grade and used without further purification (S1 Fig).