Background/Objectives: Acridine, an aromatic heterocyclic compound, serves as a basis for the synthesis of potent bioactive derivatives, displaying a broad spectrum of biological activity, such as antibacterial, antitumor, and antiparasitic activity. With the ability to undergo various types of electrophilic substitutions, introducing different side chains could lead to compounds being active towards various and potentially multiple biotargets. Toxoplasma gondii, a ubiquitous protozoan parasite with worldwide distribution, poses a major health threat, particularly in immunocompromised patients and fetuses. Current treatment options for toxoplasmosis are scarce, with notable limitations, especially regarding side myelotoxicity and inactivity towards T. gondii cysts, causing a need for novel drug candidates. The aim of this study was to evaluate selected N-(9-acrydinil) amino acid derivatives as potential anti-T. gondii agents. Methods: Synthesis of new derivatives was performed using a two-step method, with the initial mixing of 9-chloroacridine with methanol and sodium alkoxide solution and subsequent adding of appropriate amino acids. Cytotoxicity of the tested compounds was evaluated on the Vero cell line using a MTT assay, while their anti-T. gondii activity was investigated using T. gondii RH strain tachyzoites. Results: CC₅₀ values of the derivatives ranged from 41.72 to 154.10 µM. Anti-T. gondii activity, displayed as a reduction in the number of viable tachyzoites compared to the untreated control, ranged from 0 to 33.3%. One of the derivatives displayed activity comparable to the standard treatment option while retaining acceptable cytotoxicity. Esterification, presence of aromatic substituents and the length of the amino acid side chain were identified as key factors that affect both toxicity and activity of these derivatives. Conclusions: Promising results obtained throughout this study provide guidelines for further structural modifications of N-(9-acrydinil) amino acid derivatives in order to synthesize drug candidates competitive to standard treatment options for toxoplasmosis.

According to the WHO, echinococcosis is a neglected tropical disease of global importance. The Russian Federation (R.F.) is traditionally considered an endemic area of echinococcosis. This study aims to analyze the state of human infection in the R.F. in the 2000–2021 period, for which there is not enough consolidated data. Epidemiological data on human echinococcosis in the R.F. from 1 January 2000 to 31 December 2021 were collected through literature research (both published and grey literature) and official reports. From the 2022 selected records, 12 full-text articles, three doctoral dissertations, and 17 official reports were analyzed, all of which met the criteria for inclusion in the study. In the R.F., in the period from 2000 to 2021, echinococcosis (cystic (C.E.) and alveolar (A.E.) echinococcosis) has been continuously registered in humans (0.4–0.22 cases/100,000 inhabitants). Until 2013, the incidence of echinococcosis did not change (Pearson’s r (N = 13) = 0.288, p = 0.340), but in the period 2013–2021 it decreased significantly (Pearson’s r (N = 9) = −0.709, p = 0.032). In that period, the incidence of C.E. decreased significantly (Pearson’s r (N = 9) = −0.717, p = 0.035), while the incidence of A.E. did not change (Pearson’s r (N = 9) = −0.518, p = 0.154). The infection is registered annually in 30 out of 86 federal units. The C.E. infection rate was significantly higher in the European part (0.46/100,000 population) (2 = 33,783. r < 0.00001) than in the Asian part of the R.F. (0.32/100,000 population), where A.E. was more widespread. Within the European part, the frequency of C.E. infection was significantly higher in the southern (0.70/100,000 inhabitants) (χ² = 806.67, p < 00001) than in the central and northern parts (0.25/100,000 inhabitants). The incidence of C.E. per federal district was positively correlated with rural population representation (Pearson’s r (N = 8) = 0.866, p = 0.005). Every year, although in small numbers, deaths caused by echinococcosis (in the period 2009–2020—66 deaths) were registered in the R.F., significantly more often caused by A.E. than C.E. (χ² = 39.4401, p < 0.00001). Our results indicate that, between 2000 and 2021, echinococcosis was still generally endemic in the R.F. The incidence of C.E. has demonstrated a decreasing trend, especially after 2014, while the rate of A.E. remained unchanged.