The first synthesis of 2-methyl-6-pentadecyl-Δ^1,6-piperideine (1), a major alkaloid of the piperideine chemotype in fire ant venoms, and its analogues, 2-methyl-6-tetradecyl-Δ^1,6-piperideine (2) and 2-methyl-6-hexadecyl-Δ^1,6-piperideine (3), was achieved by a facile synthetic method starting with glutaric acid (4) and urea (5). Compound 1 showed in vitro antifungal activity against Cryptococcus neoformans and Candida albicans with IC₅₀ values of 6.6 and 12.4 μg/mL, respectively, and antibacterial activity against vancomycin-resistant Enterococcus faecium with an IC₅₀ value of 19.4 μg/mL, while compounds 2 and 3 were less active against these pathogens. All three compounds strongly inhibited the parasites Leishmania donovani promastigotes and Trypanosoma brucei with IC₅₀ values in the range of 5.0–6.7 and 2.7–4.0 μg/mL, respectively.

中文翻译：

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火蚁毒生物碱为基础的2-甲基-6-烷基^-Δ1,6-哌啶类化合物的合成及抑菌评价

的第一合成2-甲基-6-十五烷基Δ ^1,6 -piperideine（1），在火蚁毒液的piperideine化学型的主要生物碱，和其类似物，2-甲基-6-十四烷基Δ ^1,6通过戊二酸（4）和尿素（5）开始的简便合成方法获得-哌啶（2）和2-甲基-6-十六烷基^-Δ1,6-哌啶（3）。化合物1对IC卡_50的新隐球菌和白色念珠菌具有体外抗真菌活性。值分别为6.6和12.4μg/ mL，对万古霉素耐药的粪肠球菌的抗菌活性为IC ₅₀值为19.4μg/ mL，而化合物2和3对这些病原体的活性较低。所有三种化合物强烈抑制寄生虫杜氏利什曼原虫前鞭毛体和布氏锥虫带IC _50倍中的分别5.0-6.7和2.7-4.0微克/毫升的范围内，的值。