## 4 Conclusions  
In conclusion, we have performed a synthesis of two groups of heterocyclic benzimidazole derivatives--methanamines **4a-c** and hydrazones **6a-c--**as potential therapeutics for trichinellosis. Among the various methods available for the synthesis of azomethines of 2-aminobenzimidazole, we applied two different approaches and compared them in terms of reaction time and product yield. The addition of a 5% aqueous NaOH solution to the reaction mixture proved to be the more efficient method, as the reaction proceeded smoothly at room temperature within 2 h. Notably, both methods afforded the final products **4a-c** in comparable yields. Newly synthesized benzimidazole, being heterocyclic moieties, were evaluated for their in vitro anthelmitic activity against isolated _T. spiralis_ ML. Similar to our previous results the tested benzimidazole exhibited higher activity than albendazole at studied concentrations. The compound **4a** showed remarkable efficacy, comparable to that of the commercial anthelmitic drug ivermectin--a 54.5% larvicidal effect at a concentration of 50 \(\upmu\)g/mL after 24 h and an 80.5% effectiveness at a concentration of 100 \(\upmu\)g/mL after 48 h of incubation. In addition, an SAR of the derivatives in both chemical series was discussed. The tested methaniantimes **4a-c**, bearing thiophene moiety, exhibited greater larvicidal activity than the hydrazone analogs. This suggests that the synergistic integration of benzimidazole and thiophene pharmacophores within one structure enhances antiparasitic efficacy. However, there was a 23% decrease in anthelmitic activity when the -N=CH-linker connecting the benzimidazole to the thiophene core in compound **4a** was replaced by -NH-N=CH- in hydrazone **6a**. This result suggests that methanimines have enhanced _T. Spiralis_ larvicidal activity compared to hydrazones when all other structural features are held constant. Studies on the ability of the investigated benzimidazole derivatives to modulate microtubule polymerization show that all of the tested compounds, except compound **6a**, exhibit only a minor effect on tubulin polymerization. This result suggests that alternative mechanistic properties, such as modulation of mitochondrial function through ultrastructural changes in mitochondria, or inhibition of certain enzymes in the mitochondrial membrane, must be considered in further studies of the anti-trichinella effect. The preliminary in silico evaluation of the physicochemical, pharmacokinetic and medicinal chemistry parameters of the compounds suggested the overall druglikeness, bioavailability and ability to cross the BBB of five of the synthesized heterocyclic benzimidazole, making them suitable for future applications as neutotthrichinellosis agents.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app15126758/s1](https://www.mdpi.com/article/10.3390/app15126758/s1)]([https://www.mdpi.com/article/10.3390/app15126758/s1](https://www.mdpi.com/article/10.3390/app15126758/s1)). Figures S1-S17. IR, NMR, and HRMS (ESI) spectra of the synthesized compounds. Figures S18-S24. Bioavailability-radars computed by the SwissADME web tool for the synthesized compounds and albendazole. Figure S25. Tubulin (final 54 \(\upmu\)M) in the presence of 10 \(\upmu\)M of compounds **6a** (a), and **6b** (b).  
Conceptualization, K.A. and N.G.; investigation, K.A., G.P.-D., D.V., M.G., D.Y. and N.G.; methodology, K.A., M.G. and D.V.; supervision, K.A. and N.G.; visualization, K.A.; writing--original draft, K.A., G.P.-D., D.V., M.G., D.Y. and N.G.; writing--review and editing, K.A. and N.G. All authors have read and agreed to the published version of the manuscript.  
This study is funded by the European Union--NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, project No. BG-RRP-2.004-0002, \"BiOrgaMCT\".  
Not applicable.  
The data presented in this study are available in article.  
The authors declare no conflict of interest.