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The present work aimed to evaluate different conditions to perform monobromination reactions of α,ω‐diols using HBr. Three solvents were tested, toluene, isooctane, 1,2‐dichloroethane, in two distinct molar proportions between 1,8‐octanediol and HBr (1:1 and 1:2 equivalents). All reactions occurred under reflux. After stablishing the best reactional conditions, assays with four symmetric α,ω‐diols, 1,6‐hexanediol; 1,7‐heptanediol; 1,8‐octanediol; and 1,10‐decanediol, with 2 eq. HBr in 1,2‐dichloroethane, were conducted. Using toluene as solvent lead to the best reaction yields (81‐95%), producing the least amount of unwanted dibrominated product. Reactions in 1,2‐dichloroethane gave similar results to the ones with toluene when 2 eq. HBr were used. The lowest reactional efficiency registered in these assays occurred in isooctane, forming the highest amount of dibromide. Diols 1,7‐heptanediol and 1,8‐octanediol showed the best results under the conditions studied, in 1,2‐dichloroethane. [ABSTRACT FROM AUTHOR]

Mosquitoes of the Aedes genus are responsible for transmitting many vector-borne viral diseases worldwide. Hundreds of thousands of people die annually from vector-borne diseases, including West Nile fever, dengue, tick-borne diseases, yellow fever, chikungunya, Rift Valley fever, and Zika. Billions of people are at the risk of infection on all continents, which is a cause of international concern. Therefore, new vector-control methods are essential for mitigating these illnesses. The bioactive hydrocarbons isolated from Xylopia langsdorfiana St. Hilaire & Tulasne are trachylobanes, a rare class of diterpenes found in the n -hexane fraction of the stem and leaf ethanolic extracts. These were tested against Ae. aegypti fourth-instar larvae over 48 h of exposure, with LC 50 values ranging from 19.84 to 72.9 µg/mL, comparable to that of the positive control. The findings highlight the potential of Xylopia langsdorfiana St. Hilaire & Tulasne metabolites for controlling the main vectors of arthropod-borne viruses.