Silica 60 rp 18 f254s aluminum sheet

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).

Before biological evaluation, NMR experiments (1D and 2D) were performed on a Varian Dual Broadband Probe 400 MHz, Bruker Avance III 600, or Bruker DRX-500 and 400 MHz spectrometer using pyridine-d₅, CD₃OD, or DMSO-d₆ as solvents to identify the isolated compounds. The internal index for modification was the solvent peaks. On a mass spectrometer (Agilent Technologies 6200 series), negative and positive ion modes of mass spectra were observed. To measure the precise rotations, an automatic polarimeter IV was used. UV spectra were recorded by a Varian Cary 50 Bio UV–visible spectrophotometer. Column chromatography was performed using a flash silica gel and reversed-phase C-18. Analytical TLC was performed on a silica gel F254 aluminum sheet (20 × 20 cm, Fluka) or a Silica 60 RP-18 F254S aluminum sheet (20 × 20 cm, Merck), and detection was performed using UV-254 nm. Next, 1% vanillin in concentrated H₂SO₄-EtOH (10:90) was sprayed and then heated with a heat gun to visualize the spots. Analytical-grade solvents (Fischer Chemicals) were used in the purification and isolation procedures.