## 3 Results  
### Chemistry  
In our current research, we managed to synthesize fifteen hydrazide-hydrazones of phenylacetic acid **(2-16)**. Hydrazide of phenylacetic acid **(1)** was used as a starting  
\begin{table}
\begin{tabular}{l c c c c} \hline  & \(R_{\rm M0}\) & \(S\) & \(r^{2}\) & \(\varphi\) \\ \hline
**Acetonitrile-Water** & & & & \\ \hline
2-aminophenol & 1.1768 & \(-\)0.02 & 0.9964 & 54.37 \\ salicamide & 1.2269 & \(-\)0.03 & 0.9970 & 44.77 \\
**4-**dimethylaminebenzaldehyde & 1.5319 & \(-\)0.02 & 0.9843 & 62.20 \\ eugenol & 2.0104 & \(-\)0.03 & 0.9879 & 62.44 \\ thymol & 2.4306 & \(-\)0.04 & 0.9890 & 68.33 \\ phenyl salicate & 2.9514 & \(-\)0.04 & 0.9873 & 79.68 \\ \hline
**1.4-Dioxane-Water** & & & & \\ \hline
2-aminophenol & 1.0844 & \(-\)0.02 & 0.9916 & 47.21 \\ salicamide & 0.9964 & \(-\)0.02 & 0.9957 & 45.60 \\
4-dimethylaminebenzaldehyde & 1.6406 & \(-\)0.03 & 0.9928 & 56.20 \\ eugenol & 1.9741 & \(-\)0.03 & 0.9940 & 66.90 \\ thymol & 2.5440 & \(-\)0.04 & 0.9828 & 69.90 \\ phenyl salicate & 3.6480 & \(-\)0.05 & 0.9940 & 73.84 \\ \hline
**Methanol-Water** & & & & \\ \hline
2-aminophenol & 0.9785 & \(-\)0.02 & 0.9975 & 58.90 \\ salicamide & 1.1377 & \(-\)0.02 & 0.9817 & 56.60 \\
4-dimethylaminebenzaldehyde & 2.1143 & \(-\)0.03 & 0.9891 & 75.02 \\ eugenol & 2.7002 & \(-\)0.04 & 0.9937 & 75.91 \\ thymol & 3.2151 & \(-\)0.04 & 0.9957 & 80.56 \\ phenyl salicate & 4.2259 & \(-\)0.05 & 0.9724 & 88.04 \\ \hline \end{tabular} \(\varphi\) is the amount of organic modifier in the mobile phase. \(R_{\rm M0}\) and \(S\) are the intercept and slope of the linear regression equation, respectively. \(r^{2}\) is the correlation coefficient.  
\end{table}
Table 1: The logP values from the literature [34] and the calculated \(R_{\rm M0}\) values for the reference substances.  
compound, which produced corresponding acylhydrazones of this acid **2-16** in condensation reactions with substituted appropriate aromatic aldehydes. Microwave-assisted synthesis consisted of the heating of reagents in the microwave synthesizer in specific conditions (power of microwave--300 W, time of the reaction--7 min, temperature--155 \({}^{\circ}\)C) (Scheme 1).  
Among synthesized compounds **2-16**, acylhydrazones **2-6**, **13** and **16**[40; 41; 42; 43; 44; 45; 46] are known in scientific literature, but they were evaluated for the first time against a wide panel of microorganisms.  
The yields of the performed condensation reactions were in the range of 37-95%. The acylhydrazzone **7**--\(N^{\prime}\)-[(_E_)-(5-chloro-2-hydroxy-3-iodophenyl)methylidene]-2-phenylaceto hydrazide was synthesized with the lowest yield (37%), whereas compound **3**--\(N^{\prime}\)-[(_E_)-(3,5-dibromo-2-hydroxyphenyl)methylidene]-2-phenylacetohydrazide was synthesized with the highest yield (95%).  
The melting points of synthesized compounds **2-16** were within the range of 134-282\({}^{\circ}\)C. The lowest melting temperature (134-136 \({}^{\circ}\)C) was recorded for acylhydrazone **11**: \(N^{\prime}\)-[(_E_)-(3-ethoxy-2-hydroxyphenyl)methylidene]-2-phenylacetohydrazide, whereas compound **5**: \(N^{\prime}\)-[(_E_)-3,5-dichloro-2-hydroxyphenyl)methylidene]-2-phenylacetohydrazide, was characterized by the highest one (282 \({}^{\circ}\)C).  
The IR, \({}^{1}\)H NMR and \({}^{13}\)C NMR spectroscopies were used to establish the chemical structures of the obtained acylhydrazones of phenylacetic acid **2-16**. Examples of IR, \({}^{1}\)H NMR and \({}^{13}\)C NMR spectra are presented in Supplementary Materials (Figures S1-S9).