Semipreparative HPLC equipment consisted of a 1090 Win system, a PV5 ternary pump The LTQ-Orbitrap Velos mass spectrometer (Thermo Fisher Scientific, San Jose, CA, USA) was equipped with a heated electrospray interface (HESI) in positive and negative ionization modes. The MS scan range was performed in the FT cell and recorded within a window between 150-2000 m/z. The mass resolution was set at 105,000, and the ion spray voltage was -2.5/+3.5 kV in the positive/negative ionization mode. The ionization mode used the following parameters: N2 was used as a nebulizer gas and set at 18 arbitrary units (sheath Undesired hydrolysis to form PA was suppressed by size type and mixing conditions and supplemented with CaCl2 . In this work, almost no byproduct, i.e., PA, was detected after the reaction by MS.