## 3 Results
### Stability of Protein-Ligand Complexes
#### 3.9.1 Andrographin and WT-EGFR Complex
\begin{table}
\begin{tabular}{p{108.4 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Compound Name** & **BE (kcal/mol)** & **Hydrogen Bond Interactions (No. of Interactions)** & **Van der Waals, Pi-Alkyl, CH, Pi-Cation, Pi-Sigma, Pi-Fi Stacked, Pi-Pi T-Shaped Interactions (No. of Interactions)** & **Active Sites Residues within Interactions** & **No. of Interactions** \\ \hline Kaempreferol-7- Glucoside & \(-\)8.8 & Asp105 \(\ldots\) OH, Thr95 \(\ldots\) OH, Gln96 \(\ldots\) OH & Val31, Leu149, Leu23 (3), Cys102 & Thr95, Gln96 \(\downarrow\) 5 \\ \hline Herbacetin & \(-\)8 & Thr95 \(\ldots\) OH, Met98 \(\ldots\) OH (2), Gly101 \(\ldots\) OH & Leu23 (2), Leu149 (2), Val31 (2), Lu23, Ala48 & Thr95, Met98, Gly101, Leu23, Ala48 & Thr95, Met98, Gly101, Leu23, Ala48 & Thr \\ \hline Gossypetin & \(-\)8.5 & Met98\(\ldots\)OH, Thr95 \(\ldots\) OH (2) & Thr159, Ala48, Val31 (2), Leu149 (2), Leu23 (2) & Thr95, Met98, Leu23, Ala48 & 6 \\ \hline Andrographidine C & \(-\)8.3 & Thr95 \(\ldots\) OH (2), Gln96 \(\ldots\) OH, Gly26 & Arg146, Val31, Leu149, Leu23 (2), Cys102 (2), Asp105 & Thr95, Gln96, Leu23, Cys102 & 7 \\ \hline
5-Hydroxy-7,8,2\({}^{\prime}\)- Trimethoxyflavone (Andrographin) & \(-\)8.3 & Met98 \(\ldots\)\(\ldots\)O, Met98 \(\ldots\)OH & Thr159, Lys50, Val31 (2), Ala48 (2), Leu149 (2), Leu23 (2), Leu149, Asp105 & Thr98, Lys50, Ala48, Leu23 & 7 \\ \hline Skullcapflavone I & \(-\)8.1 & Met98 \(\ldots\)\(\ldots\)O, Met98 \(\ldots\) OH & Thr159, Val31 (2), Lys50, Ala48 (2), Leu23 (2), Leu149, Asp105 & Thr98, Lys50, Ala48, Leu23 & 7 \\ \hline \(2^{\prime}\)-hydroxy-5,7,8-trimethoxyflavone & \(-\)8.1 & Nil & Gly101, Leu23 (2), Leu149 (2), Val31 (2), Gly24 & [PERSON] & 2 \\ \hline \(5\),4\({}^{\prime}\)-dihydroxy-7,8,2\({}^{\prime}\)-tetamethoxyflavone & \(-\)7.7 & [PERSON] & [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] (2), [PERSON], [PERSON] (2), [PERSON] (2), [PERSON] & [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] & 7 \\ \hline
5-hydroxy-7,8,2\({}^{\prime}\)-tetamethoxyflavone & \(-\)8.2 & Met98 \(\ldots\)\(\Rightarrow\)O & [PERSON] (2), [PERSON], [PERSON] (2), [PERSON], [PERSON] (2), [PERSON] (2), [PERSON] & Met98, Lys50, Ala48, Leu23 & 5 \\ \hline
5-hydroxy-7,8,2\({}^{\prime}\),5\({}^{\prime}\)-tetamethoxyflavone & \(-\)8.4 & Met98 \(\ldots\)\(\Rightarrow\)O & Val31 (2), Lys50, Thr159, Ala48, [PERSON] (2), [PERSON] (2), [PERSON] & Met98, Lys50, Ala48, [PERSON] & 5 \\ \hline
5-hydroxy-7,8,2\({}^{\prime}\),3\({}^{\prime}\)-tetamethoxyflavone & \(-\)8.3 & Nil & Lys80, [PERSON] (2), Val31 (2), Gln96, Ala48, [PERSON], [PERSON] (2), Cys102 (2) & Lys50, Gln96, Ala48, Leu23 & 5 \\ \hline Wightin & \(-\)8.3 & Met98 \(\ldots\)\(\Rightarrow\)O, Met98 \(\ldots\)OH & Val31 (2), Lys50, Thr159, Ala48 (2), [PERSON] (2), Leu149 (2), Asp105 & Met98, Lys50, [PERSON], Ala48, Gln96 & 7 \\ \hline
5-Hydroxy-7,8,2\({}^{\prime}\),3\({}^{\prime}\)-Tetamethoxyflavone & \(-\)8.6 & Met98 \(\ldots\)\(\Rightarrow\)O & Asp105, Val31 (2), Thr159, Lys50, [PERSON] (2), [PERSON] (2), Ala48, Gln96 & 7 \\ \hline Altisin & \(-\)7.8 & Met98 \(\ldots\) O- & Val31 (2), Ala48, Leu149 (2), Leu23 (2) & Met98, Ala48, Leu23 & 4 \\ \hline \hline \end{tabular} BE, binding energy.  
\end{table} 
Table 4: Binding energy and molecular interactions of phytocompounds with WT–EGFR protein target. Figure 5: Intermolecular interactions of (**A**) Andrographin and (**B**) Gossypetin with WT–EGFR; (1) 2D representation and (2) 3D representation of compounds within the binding pocket. Figure 6: Andrograph with WT–EGFR 100 ns MD production run. (**A**) RMSD plot depicting the “Protein Backbone”. (**B**) Plot depicting the docked complex stability “ligand–protein complex RMSD”. (**C**) Plot depicting the stability of “ligand w.r.t. ligand”. Figure 7: EGFR–Andrographin complex 100 ns MD production run. (**A**) Protein RMSF plot. (**B**) A gyration plot depicting the extendedness of a ligand. (**C**) A gyration plot of protein during a 100 ns production run.