6200 series mass spectrometer

Optical rotations were measured in MeOH using AUTOPOL II Automatic Polarimeter (Rudolph, Hackettstown, NJ, USA). ECD spectra were collected using Olis DSM 20 CD digital spectropolarimeter (Bogart, GA, USA). IR spectra were determined on an Agilent Technologies Cary 630 FTIR. UV spectra were measured on a Thermo Scientific Evolution 201 UV-visible spectrophotometer. NMR experiments were carried out on a Bruker Avance III 400 MHz spectrometer using CD₃OD as a solvent and methanol residue signals were used as the internal standard. An Agilent Technologies 6200 series mass spectrometer was employed to acquire mass data. Column chromatography (CC) was performed over flash silica gel (SiliaFlashV^®P60, SiliCycle Inc., USA). Analytical TLC was carried out on silica gel F₂₅₄ aluminum sheet (20 cm × 20 cm, SiliCycle, Canada) or reversed phase C-18 aluminum sheet (20 cm × 20 cm, Sorbent Tech., USA). The detection of the spots was made possible by visualization under UV-254 nm and by spraying with 1% vanillin in H₂SO₄–EtOH (10 : 90), followed by heating. Analytical grade solvents (Fischer chemicals) were used for the isolation and purification procedures.

Both 1D and 2D NMR experiments were measured on Varian 400 MHz spectrometer. The samples were dissolved in deuterated methanol (CD₃OD). The sample peaks were adjusted with the reference to the solvent peak. The high-resolution mass spectra were measured on Agilent Technologies 6200 series mass spectrometer. Stationary phases for column chromatography (CC); flash silica gel of particle size 32-63μ (Dynamic adsorbents Inc.) and RP-18 (Polar bond, J. T. Baker) were used. Silica gel F₂₅₄ aluminum sheet (Fluka) and Silica 60 RP-18 F₂₅₄S aluminum sheet (Merck) were employed for performing TLC. The spots were noticed under UV-254 and 365 nm or after spraying with 1% vanillin/H₂SO₄ followed by heating for 2 min. All solvents used through the chromatographic process were of analytical grade (Fischer Chemicals).