C23-3 C23-4
Figure1 Four most stable conformations of probe C23
To illustrate the reaction sites within the probe molecule, the electrostatic potential of C23-1 was analyzed using Multiwfn 3.7 from the wave function generated under wB2GP-PLYP/def2-TZVP combination from ORCA program. The electrostatic potential of C23-1 was as shown in Figure2. Several local maximum and minimum values of electrostatic potential except those within the N-CH2-CH3 groups were depicted in the Figure2 which showed the potential reaction sites with the HSA. The results were agreed with the previous work.7