6224 toflc ms mass spectrometer

1D and 2D NMR spectra were acquired using a 500 or 600 MHz Bruker AVANCE spectrometer (Billerica, MA, USA) using a cryoprobe and CDCl₃ as solvent. Mass spectra were measured with a LC/MS Waters Alliance mass spectrometer (Malford, MA, USA) equipped with a 2695 HPLC module, 996 photodiode array detector, and Micromass Quattro triple quadrupole mass spectrometer with ESI under the positive mode. High-resolution electrospray ionization mass spectroscopy (HRESIMS) was recorded on an Agilent Technologies (Santa Clara, CA, USA) 6224 TOFLC/MS mass spectrometer. TLC was carried out on pre-coated silica gel plates (silica gel 60 F-254, Merck KGaA, Darmstadt, Germany). Spots were visualized by spraying with 20% sulfuric acid in ethanol followed by heating. Preparative HPLC was performed on a Waters 1528 binary pump and 2487 diode array detector system using a Phenomenex (Torrance, CA, USA) Kinetex 5 μm C₁₈ 250 × 21 mm and a Phenomenex Luna 5 μm C₁₈ 250 × 21 mm columns. Isobutyric anhydride, pivalic anhydride, isovaleric anhydride, cyclopropane chloride, formic acid, 4-dimethylaminopyridine (DMAP), and N,N-diisopropylethylamine (Hünig’s base) were obtained from Sigma-Aldrich (St. Louis, MO, USA). Anthraquinone-2-carbonyl chloride was purchased from TCI America (Portland, OR, USA).

Optical rotations were measured on a Rudolph Research Autopol III automatic polarimeter. NMR data were obtained on a Varian VNMR spectrometer (500 MHz for ¹H, 125 MHz for ¹³C) with a broad band probe at 25 ± 0.5 °C. High-resolution electrospray ionization mass spectrometry (HRESIMS) was performed on an Agilent Technologies 6224 TOFLC/MS mass spectrometer. Prepative HPLC separations were performed on a Shimadzu system using a SCL-10A VP controller and a Gemini 5 μm C18 column (110 Å, 250 × 21.2 mm) or a Kinetex 5 μm F5 column (110 Å, 250 × 21.2 mm) with flow rate of 10 mL/min. All solvents were of ACS grade or better.

1D and 2D NMR spectra were acquired using a 500 or 600 MHz Bruker AVANCE spectrometer (Billerica, MA, USA) using a cryoprobe and CDCl₃ as solvent. Mass spectra were measured with an LCMS composed of a Waters Alliance mass spectrometer (Malford, MA, USA) equipped with a 2695 HPLC module, 996 photodiode array detector as well as a Micromass Quattro triple quadrupole mass spectrometer under positive mode ESI conditions. High-resolution electrospray ionization mass spectrometry (HRESIMS) was performed on an Agilent Technologies (Santa Clara, CA, USA) 6224 TOFLC/MS mass spectrometer. TLC was carried out on pre-coated silica gel plates (silica gel 60 F-254, Merck KGaA, Darmstadt, Germany). Spots were visualized by spraying with 20% sulfuric acid in ethanol followed by heating. Preparative HPLC was performed on a Waters 1528 binary pump and 2487 diode array detector system using a Phenomenex (Torrance, CA, USA) Kinetex 5 μm C₁₈ 250 × 21 mm and a Phenomenex Luna 5 μm C₁₈ 250 mm × 21 mm columns with flow rate of 8 mL/min. Semi-preparative HPLC separations were performed on a Waters 1525 system using a 2998 PDA detector and Gemini 5 μm C₁₈ column (110 Å, 250 mm × 10.0 mm) with a flow rate of 4 mL/min.