Toxicological evaluation of zidovudine and novel chalcogen derivatives in Drosophila melanogaster.

Zidovudine (AZT) is the most commonly prescribed antiviral drug for the treatment of human immunodeficiency virus (HIV) infection. However, its chronic administration causes toxic side effects limiting its use. This study aimed to evaluate the toxicity of different concentrations of AZT and novel chalcogen derivatives (7A, 7D, 7G, 7K, 7M) on locomotion, mitochondrial dysfunction, acetylcholinesterase (AChE) activity, and production of reactive oxygen species (ROS) in adult Drosophila melanogaster. Our results show that AZT and its derivative 7K at a concentration of 10 µM impaired flies' locomotor behavior. Furthermore, AZT and the derivatives 7K, 7A, and 7M induced mitochondrial dysfunction observed by a decrease in oxygen flux through mitochondrial complexes I and II. Neither of the compounds tested affected AChE activity or ROS production in flies. According to these data, AZT derivatives presented the following decreasing order of toxicity: 7K > AZT > 7G > 7A > 7M > 7D. Based on the chemical structure, it is possible to infer that the presence of the seleno-phenyl group in 7A and 7G increases their toxicity compared to compounds 7D and 7M. In addition, compounds 7G, 7M, and 7K with three carbon atoms as spacer were more toxic than analogs containing one carbon atom (7A and 7D). Finally, the insertion of a p-methoxyl group enhances toxicity (7K). Based on these results, excepting 7K, all other chalcogen derivatives presented lower toxicity than AZT and are potential drug candidates.

Chalcogenium-AZT Derivatives: A Plausible Strategy To Tackle The RT-Inhibitors-Related Oxidative Stress While Maintaining Their Anti- HIV Properties.

BACKGROUND: This study presents the synthesis and multi-target behavior of the new 5'-hydroxy-3-(chalcogenyl-triazoyl)-thymidine and the biological evaluation of these compounds as antioxidant and anti-HIV agents. OBJECTIVE: Antiretroviral therapy induces oxidative stress. Based on this, this manuscript's main objective is to prepare compounds that combine anti-HIV and antioxidant activities. METHODS: The compounds were prepared from commercially available AZT through a copper-catalyzed Huisgen 1,3-dipolar cycloaddition exploiting the AZT azide group and chalcogenyl alkynes. RESULTS: The chalcogenium-AZT derivatives were obtained in good yields via click chemistry. The compounds evaluated showed antioxidant and anti-HIV activity. Additionally, in vivo toxicity of this class of compounds was also evaluated. The representative nucleoside did not change the survival, behavior, biochemical hepatic, or renal markers compared to the control mice. CONCLUSION: Data suggest the feasibility of modifying the AZT nucleus with simple organohalogen fragments, exploring the reactivity of the azide group via 1,3-dipolar Huisgen cycloaddition reaction. The design of these new compounds showed the initially desired biological activities.