Here, we demonstrate the divergent synthesis of symmetrical or unsymmetrical tetrathiadiindoles and pentathiepino[6,7-b]indoles from indoles and elemental sulfur under metal-free conditions. These transformations probably involve a selective cyclization process of specific indole sites with polysulfur fragments which are in situ generated from elemental sulfur. This work features simple operation, metal-free nature, wide substrate scope, readily available starting materials, and feasible synthesis of valuable products. Furthermore, this method enables the direct assembly of active molecules that show anti-fungal activity and could be used as FIV inhibitors. Notably, temperature and oxidant play crucial roles in the selective synthesis of polythioindole derivatives.

中文翻译：

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无金属条件下以元素硫为多硫源的发散合成聚硫吲哚

在这里，我们证明了在无金属条件下由吲哚和元素硫不同合成对称或不对称四硫二吲哚和五硫杂[6,7- b ]吲哚。这些转化可能涉及特定吲哚位点与由元素硫原位产生的多硫片段的选择性环化过程。该工作具有操作简单、非金属性质、底物范围广、起始原料易得、有价值产品合成可行的特点。此外，该方法能够直接组装具有抗真菌活性的活性分子，并可用作 FIV 抑制剂。值得注意的是，温度和氧化剂在聚硫吲哚衍生物的选择性合成中起着至关重要的作用。