The DAD was set to 520, 330, and 280 nm to record peaks, and UV−vis spectra were recorded from 190 to 800 nm. A Bruker Daltonik (Bremen, Germany) maXis Q-TOFHRMS instrument with an ESI source was used for mass analysis. The instrument was operated by the microTOF control (Bruker Daltonik) software package. Negative ion mode and an m/z
range of 100−2000 were selected during operation