1100 series lc msd spectrometer

All reactants and reagents were purchased from Alfa Aesar and Sigma–Aldrich as “synthesis grade.” Chemical reactions were monitored by analytical thin-layer chromatography (TLC) using several solvent systems with different polarity on Merck Silica Gel 60 F₂₅₄ (0.040–0.063 mm) with detection by UV. Merck Silica Gel 60 (0.040–0.063 mm) was used for column chromatography. ¹H NMR and ¹³C NMR spectra were recorded on a Varian 300 MHz (USA) spectrometer using the residual signal of the deuterated solvent as internal standard. Splitting patterns of signals are indicated as singlet (s), doublet (d), triplet (t), multiplet (m), broad (br), and doublet of doublet (dd). The values of chemical shifts (δ) are reported in ppm and coupling constants (J) in hertz (Hz). Electrospray ionization-mass spectrometric (ESI-MS) were acquired with an Agilent 1100 series LC/MSD spectrometer equipped with a multimode ion source and by using methanol as solvent.

The supernatant extract was applied to a reverse phase silica gel Polygoprep 100–50 C18 VFC (vacuum flash chromatography) system, using stepwise gradient elution from H₂O to MeOH. The active fraction (2.72 g) was eluted with H₂O-MeOH 1:9 and was subjected to preparative reversed-phase HPLC equipped with a Symmetry C18 column (19 × 150 mm, 7 μ) and using a linear gradient of H₂O/CH₃CN from 5% to 100% of CH₃CN in 60 min at a flow rate of 15 mL/min. The active fractions were further purified by a semi-preparative HPLC on a Symmetry C18 column (7.8 × 150 mm, 7 μ) using isocratic elution with H₂O/CH₃CN 55:45 at a flow rate of 3 mL/min to yield 80 mg of the pure compound 1, 94 mg of compound 2 and 44 mg of compound 3. NMR spectra were recorded on a Varian “Unity 500” spectrometer at 500/125 MHz (¹H/¹³C) and on a Varian Unity 400 spectrometer at 400/100 MHz (¹H/¹³C). Chemical shifts were reported in ppm using residual CDCl₃ (δ 7.26 ppm for ¹H and 77.0 ppm for ¹³C) as an internal reference. Two-dimensional experiments COSY, TOCSY, HSQC, and HMBC were performed using standard pulse sequences. Data were processed using MestReNova 14.0.1 software. (+)-ESIMS spectra obtained on an Agilent 1100 Series LC/MSD spectrometer. High-Resolution Mass Spectroscopy (HRMS) was performed on an Agilent 6230 TOF LC/MS system using the ESIMS technique.