## Results and Discussion
### In Silico Drug Likeness Property Analysis  
In modern drug discovery approaches, evaluation of absorption, distribution, metabolism and excretion (ADME) of drug candidates impose significant value to the rational drug design. In vitro and in vivo ADME prediction has now become faster and more accurate with the computational chemistry tools which has been developed recently and aids the pharmaceutical industries to screen many compounds within a very short time [38]. In this experiment, we analyzed the predicted ADME values of the designed compounds (**6a-j**) and are summarized in Table 2. Since high molecular weight compounds are always less effective in terms of intestinal absorption, our synthesized compounds' (**6a-j**) molecular weight (353-418 Da) of this study are less than the established drug gefitinib (447 Da), which supports the established parameters [9; 39]. Subsequently, the studied compounds showed recommended values for hydrogen bond donor (<5) and acceptor (<10). Gefitinib showed HBD value of 1 and HBA value of 7.7 whereas the studied compounds showed HBD values of 0 (except **6c** having HBD 1) and HBA values of maximum 6.5 (compound **6a**), 6.25 (compound **6c**), 6.0 (compound **6j**) \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**No.** & **MW b** & **HBD c** & **HBA d** & **logPo/w e** & **log5 f** & **logP** & **HERGS** & **Caco-2 h** & **BBB i** & **MDCKj** & **HOA(\%) k** \\ \hline
**6a** & 382 & 0 & 6.5 & 4.77 & \(-\)5.76 & 10.2 & \(-\)7.35 & 3189 & \(-\)0.36 & 1733.1 & 100 \\
**6b** & 374 & 0 & 5.5 & 4.86 & \(-\)5.60 & 9.4 & \(-\)7.16 & 3720 & \(-\)0.02 & 5054.6 & 100 \\
**6c** & 355 & 1 & 6.25 & 3.82 & \(-\)5.07 & 11.8 & \(-\)7.13 & 1102 & \(-\)0.83 & 549.7 & 100 \\
**6d** & 418 & 0 & 5.5 & 4.87 & \(-\)5.58 & 9.5 & \(-\)7.19 & 3656 & \(-\)0.04 & 4745.7 & 100 \\
**6e** & 418 & 0 & 5.5 & 4.93 & \(-\)5.74 & 9.4 & \(-\)7.20 & 3637 & \(-\)0.02 & 5296.9 & 100 \\
**6f** & 418 & 0 & 5.5 & 4.93 & \(-\)5.72 & 9.4 & \(-\)7.19 & 3719 & \(-\)0.01 & 5433.8 & 100 \\
**6g** & 353 & 0 & 5.5 & 4.61 & \(-\)5.30 & 9.4 & \(-\)7.14 & 3754 & \(-\)0.19 & 2067.3 & 100 \\
**6h** & 353 & 0 & 5.5 & 4.67 & \(-\)5.46 & 9.4 & \(-\)7.17 & 3638 & \(-\)0.21 & 1998.3 & 100 \\
**6i** & 353 & 0 & 5.5 & 4.67 & \(-\)5.44 & 9.3 & \(-\)7.16 & 3734 & \(-\)0.20 & 2054.9 & 100 \\
**6j** & 385 & 0 & 6.0 & 5.01 & \(-\)5.93 & 9.7 & \(-\)7.38 & 3479 & \(-\)0.21 & 3246.6 & 100 \\
**Cj** & **447** & **1** & **7.7** & **4.37** & **\(-\)5.23** & **10.8** & **\(-\)7.12** & **1053** & **0.31** & **2313.1** & **100** \\ \hline \hline \end{tabular}  
* Molecular weight in Daltons (acceptable range: <500);
* Hydrogen bond donor (acceptable range: \(\leq\)5);
* Hydrogen bond acceptor (acceptable range: \(\leq\)10);
* Predicted octanol/water partition coefficient (acceptable range: –2–6.5);
* Predicted aqueous solubility, **5*
* in mol/dm\({}^{-3}\) (acceptable range: –6.5–0.5);
* Predicted IC\({}_{50}\) value for blockage of the ERG K+ channels (concern: below \(\sim\)5);
* Caco–2 value, permeability to Caco–2 (human colorectal carcinoma) cells in vitro;
* Blood–brain barrier permeability (acceptable range: \(\sim\)-0.4);
* Predicted apparent MDCKj cell permeability in nm/sec, QPPMDCK= 500 is great; *25 is poor; k Predicted human oral absorption on 0% to 100% scale (<25% is poor and \(>\)80% is high);
* IG = Gefitinib.  
\end{table} 
Table 2: Analysis of drug likeness properties and pharmacokinetic properties by QikProp for 6a-j. and other compounds **6b**, **6d-6i** having HBA values of 5.5, which indicates superior values to the gefitinib (HBA values is 7.7). In 2002, [PERSON] and [PERSON] established a parameter to check the bioavailability of the drug compound which can be determined by octanol/water partition coefficient and solubility scoring where the recommended values are \(-\)2-6.5 and \(-\)6.5-0.5 mol/dm\({}^{-3}\), respectively [40]. Compounds of this study showed scoring within the reference values including gefitinib.