1200 hplc msd mass spectrometer

All reagents and solvents
were used as purchased from commercial sources without further purification.
Flash chromatography was performed using 300-mesh silica gel. All
reactions were monitored by TLC using silica-gel plates with fluorescence
F254 and UV-light visualization. ¹H NMR spectra were recorded
on a Bruker AV-400 spectrometer at 400 MHz or a Bruker AV-500 spectrometer
at 500 MHz. ¹³C NMR spectra were recorded on a Bruker AV-500
spectrometer at 125 MHz. Coupling constants (J) are
expressed in hertz (Hz). Chemical shifts (δ) of NMR are reported
in parts per million (ppm) relative to an internal standard (TMS).
Low- and high-resolution of ESI-MS was recorded on an Agilent 1200
HPLC-MSD mass spectrometer and an Applied Biosystems Q-STAR Elite
ESI-LC-MS/MS mass spectrometer, respectively. Purities of the final
compounds, 5a–5r, were determined
to be >95% by reverse-phase high-performance liquid chromatography
(HPLC, Dionex Summit HPLC; Diamonsil C18 column, 5.0 μm, 4.6
× 250 mm, Dikma Technologies; PDA-100 photodiode-array detector;
ASI-100 autoinjector; p-680A pump). A flow rate of 1.0 mL/min was
used with a mobile phase of 90% MeOH in H₂O with 0.1% modifier
(ammonia, v/v).

Reagents and solvents were obtained from commercial suppliers and used without further purification. Flash chromatography was performed using silica gel (300–400 mesh). All reactions were monitored by TLC, silica gel plates with fluorescence F254 were used and visualized with UV light. 1H and 13C NMR spectra were recorded on a Bruker AV-400 spectrometer at 400 MHz and Bruker AV-500 spectrometer at 125 MHz, respectively (Bruker, Billerica, MA). Coupling constants (J) are expressed in hertz (Hz). Chemical shifts (δ) of NMR are reported in parts per million (ppm) units relative to internal control (TMS). The low or high resolution of ESI-MS was recorded on an Agilent 1200 HPLC-MSD mass spectrometer (Santa Clara, CA) or Applied Biosystems Q-STAR Elite ESI-LC-MS/MS mass spectrometer (Foster City, CA), respectively.

All reagents and solvents were used directly as purchased from commercial sources. Flash chromatography was performed using silica gel (200–300 mesh). All reactions were monitored by thin-layer chromatography (TLC), using silica gel plates with fluorescence F₂₅₄ and UV light visualization. ¹H NMR and ¹³C NMR spectra were recorded on a Bruker AV-400 spectrometer and Bruker AV-600 spectrometer. Coupling constants (J) are expressed in hertz (Hz). Chemical shifts (δ) of NMR are reported in parts per million (ppm) units relative to an internal control (TMS). Low resolution ESI-MS were recorded on an Agilent 1200 HPLC-MSD mass spectrometer and high resolution ESI-MS on an Applied Biosystems Q-STAR Elite ESI-LC-MS/MS mass spectrometer. HPLC instrument for purity analysis was as follows: Dionex Summit HPLC (column: AD-3, 5.0 μM, 4.6 mm × 250 mmL). A flow rate of 1.0 ml/min was used with a mobile phase of Isopropyl alcohol in Hexane.