Figure 1. Theoretical structures of free two enantiomeric S(-) and R(+) forms of CQ.
In Table 1 the properties calculated for the two enantiomeric S(-) and R(+) forms of CQ in both media can be seen by using both hybrid B3LYP/6-311++G** method. Hence, the total energy corrected and uncorrected by ZPVE is presented together with dipolar moment and volume values. The results show that the S(-) form is most stable in gas phase while the R(+) form in aqueous solution. The differences in the energy values in gas phase and aqueous solution are 1.83 and 3.67 kJ/mol, respectively.
Table 1. Calculated total energies (E ), dipole moments (ยต) and volumes (V) of S(-) and R(+) forms of chloroquine in gas phase and aqueous solution by using the B3LYP/6-311++G** Method.