2. Materials and Methods
The starting structures of all the modifications were generated by
considering the crystal structures of respective standard modifications.
Other modifications were built using molecular building and
visualization software Gaussview43. The 2D structures
of all the modifications are given in Figure 1 and the modification
details are given in Table 1. The proposed novel modifications have been
labelled as A1 to A5 in Figure 1. The complete methodology can be
divided into three sections, conformational search and identifying most
stable conformation, running quantum mechanical calculations in various
levels and quantum chemical descriptor derivation.