Liquid chromatography was carried out using an Agilent HP 1100
system coupled to ESI-MS (Agilent, Waldbronn, Germany). For the
separation a Phenomenex C18 (150×3 mm, 5 μm) (Germany) column
was used. The separation was carried out using an isocratic solvent
system consists of 18% isopropanol in methanol with 0.1% acetic acid
with a flowrate of 0.6 mL/min.Mass spectrometrywas carried out using
an Agilent HP 1100 system ESI-MS (Agilent, Waldbronn, Germany).
Other conditions of LC andMSwere the same as reported in our previous
reports