# Assessment of Bioavailability Parameters of Mono- and Bistriazole Derivatives of Propynoylbetulin
## 3 Results  
In the first step of the research, the experimental lipophilicity was determined by using the RP-TLC method. As a mobile phase, the mixture of acetone and Tris buffer was used. The concentration of acetone in the mobile phase was in the range from 60% to 90%. The obtained R\({}_{\text{f}}\) values for each compound **1**-**18** were converted to R\({}_{\text{M}}\) and R\({}_{\text{M}0}\) parameters using Equations (1) and (2), and are presented in Table 1.  
The experimental values of R\({}_{\text{M}0}\) and slope \(b\) were used to determine the hydrophobicity index according to Equation (3), and are presented in Table 1.  
The R\({}_{\text{M}0}\) parameter was converted to the lipophilicity parameter (logP\({}_{\text{TLC}}\)) using the calibration curve. As reference compounds, 4-bromoacetophenone (**A**), benzophenone (**B**), anthracene (**C**), dibenzyl (**D**), 9-phenylanthracene (**E**), and dichlorodiphenyltrichloroethane (DDT) (**F**) were used whose lipophilicity (logP\({}_{\text{lit}}\)) in the literature is in the rage from 2.43 to 6.38 [13,14]. The experimental lipophilicity of the reference compounds was determined similarly to the tested compounds **1**-**18** (Table 2). The calibration curve (Equation (4)) was obtained by linear regression between the experimental R\({}_{\text{M}0}\) parameter and lipophilicity (logP\({}_{\text{lit}}\)) in the literature. \[\text{LogP}_{\text{TLC}}=1.0878\text{ R}_{\text{M}0}+0.3972\text{ (r = 0.988; SD = 0.263),} \tag{4}\] \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Compound** & **R\({}_{\text{M}0}\)** & \(b\)** & **r** & **logP\({}_{\text{TLC}}\)** & \(\varphi_{\text{0}}\)** & **Compound** & **R\({}_{\text{M}0}\)** & \(b\)** & **r** & **logP\({}_{\text{TLC}}\)** & \(\varphi_{\text{0}}\)** \\ \hline
**1** & 5.78 & \(-\)0.06 & 0.995 & 6.68 & 90.17 & **2** & 8.09 & \(-\)0.09 & 0.992 & 9.20 & 90.09 \\
**3** & 6.15 & \(-\)0.07 & 0.997 & 7.09 & 86.86 & **11** & 7.05 & \(-\)0.08 & 0.992 & 8.07 & 86.29 \\
**4** & 6.31 & \(-\)0.07 & 0.994 & 7.26 & 86.68 & **12** & 7.15 & \(-\)0.08 & 0.993 & 8.17 & 86.04 \\
**5** & 6.29 & \(-\)0.07 & 0.993 & 7.24 & 85.12 & **13** & 6.57 & \(-\)0.08 & 0.995 & 7.54 & 83.38 \\
**6** & 6.85 & \(-\)0.08 & 0.988 & 7.85 & 87.15 & **14** & 7.75 & \(-\)0.09 & 0.994 & 8.83 & 87.18 \\
**7** & 3.67 & \(-\)0.05 & 0.988 & 4.39 & 73.11 & **15** & 3.08 & \(-\)0.05 & 0.950 & 3.75 & 59.69 \\
**8** & 4.56 & \(-\)0.06 & 0.992 & 5.36 & 78.76 & **16** & 5.68 & \(-\)0.08 & 0.998 & 6.58 & 70.65 \\
**9** & 4.44 & \(-\)0.05 & 0.994 & 5.23 & 81.92 & **17** & 4.35 & \(-\)0.06 & 0.990 & 5.13 & 75.65 \\
**10** & 5.57 & \(-\)0.07 & 0.994 & 6.46 & 85.04 & **18** & 6.59 & \(-\)0.08 & 0.987 & 7.57 & 82.89 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The experimental values of lipophilicity and hydrophobicity parameters. According to Equation (4), the experimental lipophilicity (logP\({}_{\text{TLC}}\)) of the reference compounds was calculated (Table 2). As seen in Table S1, the experimental results correlate well with the ones in the literature. In the next step, the experimental lipophilicity was compared with the calculated lipophilicity which was determined using the ALOGPs, miLogP, XLOGP2, AClogP, and XLOGP3 programs. The results are shown in Table 3.  
Lipophilicity is connected with other bioavailability parameters such as molecular mass (M), topological polar surface (TPSA), the number of acceptors (HAs) and donors (HDs) of the hydrogen bond, and the number of rotatable bonds (RTs). The research was supplemented with in silico-determined parameters responsible for the drug's permeation of the biological barrier, like Caco-2 cell (logPapp), human intestinal absorption (HIA), skin permeability (logKp), blood-brain barrier permeability (logBB), and central nervous system (logPS) penetration [56; 57; 58]. The results obtained using pkCSM software are presented in Table 4.