BACKGROUND The indole framework is considered as one of the privileged structures in the area of medicinal chemistry and drug discovery because compounds containing this framework have shown to possess a remarkable ability to bind with many receptors or proteins with high affinity. It is therefore not surprising that the indole nucleus is a frequently found moiety in many bioactive agents or drugs. Indole derivatives have also been explored or studied for their anti-tubercular properties for a long time. The growth inhibition of Mycobacterium tuberculosis (MTB) in vitro and in vivo by the gut microbiota metabolite indole propionic acid (IPA) is one of the recent examples. Notably, tuberculosis (TB), an intractable disease and a major cause of death worldwide, has caused an alarming rise in the number of TB cases recently because of two main reasons, i.e., a several-fold rise among HIV-infected patients and increased drug resistance by some bacterial strains. Thus, the identification of new agents or potential drugs against TB is urgently needed. METHODS While the specific pharmacological target or mechanism of action (MOA) for antitubercular activities has been reported for many indole derivatives, the MOA is not well defined or known for a number of indole derivatives though they were found to be active against MTB. In the current review article, we have focused on both types of indole derivatives that have shown activities against MTB. The indoles with known MOA are further segregated based on this pharmacological target reported or indicated whereas other indoles are classified based on the type of anti-TB properties shown by them. The literature for the last 20 years as well as related to up to date knowledge and information was searched on Pubmed, Google Scholar, MEDLINE, and various other databases until August 2020. RESULTS A diverse range of functionalized indole derivatives, such as indole-based alkaloids, simple indoles, fused indoles, amide/peptide derivatives of indole, isatin derivatives, etc., have been reported to possess anti-tubercular activities. The anti-tubercular activities, in silico studies (if reported) and the chemical syntheses (in most of the cases) of representative indole derivatives are presented briefly in the current article. The papers referenced by this review allow a deep analysis of the status of the indole-based anti-tubercular agents explored over the past two decades. CONCLUSION This review aims at stimulating renewed interest and effort in the discovery and development of new indole-based agents or potential drugs for the treatment of TB. The emergence of modern methods, especially those based on transition metal-catalyzed reactions, has opened up tremendous opportunities in the area of indole synthesis. The desired goal would be to have utilized these modern methodologies for the identification of potent and promising agents to fight against MTB.

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吲哚衍生物作为抗结核剂：其合成和生物活性概述。

背景技术吲哚骨架被认为是药物化学和药物发现领域的一种特权结构，因为含有该骨架的化合物已显示出具有与许多受体或蛋白质高亲和力结合的显着能力。因此，吲哚核是许多生物活性剂或药物中经常发现的部分也就不足为奇了。吲哚衍生物的抗结核特性也已被探索或研究了很长时间。肠道微生物群代谢物吲哚丙酸 (IPA) 在体外和体内抑制结核分枝杆菌 (MTB) 的生长是最近的例子之一。值得注意的是，结核病（TB）是一种顽固性疾病，也是世界范围内的主要死因，由于两个主要原因，即感染艾滋病毒的患者人数增加了几倍以及某些细菌菌株的耐药性增加，最近导致结核病病例数量惊人增加。因此，迫切需要鉴定新的药物或潜在的抗结核药物。方法 虽然已经报道了许多吲哚衍生物的抗结核活性的特定药理学靶点或作用机制 (MOA)，但许多吲哚衍生物的 MOA 没有明确定义或已知，尽管它们被发现对 MTB 具有活性。在当前的评论文章中，我们重点介绍了两种类型的吲哚衍生物，它们都显示出对抗 MTB 的活性。具有已知 MOA 的吲哚根据报告或指示的该药理学目标进一步分离，而其他吲哚则根据它们显示的抗结核特性的类型进行分类。在 Pubmed、Google Scholar、MEDLINE 和各种其他数据库中搜索了过去 20 年的文献以及与最新知识和信息相关的内容，直到 2020 年 8 月。 结果 各种功能化吲哚衍生物，例如基于吲哚的衍生物据报道，生物碱、简单吲哚、稠合吲哚、吲哚的酰胺/肽衍生物、靛红衍生物等具有抗结核活性。本文简要介绍了代表性吲哚衍生物的抗结核活性、计算机模拟研究（如果有报道）和化学合成（在大多数情况下）。本综述引用的论文可以深入分析过去二十年探索的吲哚类抗结核药物的现状。结论 本综述旨在激发人们对新的吲哚类药物或治疗结核病的潜在药物的发现和开发的兴趣和努力。现代方法的出现，尤其是那些基于过渡金属催化反应的方法，为吲哚合成领域开辟了巨大的机遇。预期的目标是利用这些现代方法来识别有效和有前途的药剂来对抗 MTB。结论 本综述旨在激发人们对新的吲哚类药物或治疗结核病的潜在药物的发现和开发的兴趣和努力。现代方法的出现，尤其是那些基于过渡金属催化反应的方法，为吲哚合成领域开辟了巨大的机遇。预期的目标是利用这些现代方法来识别有效和有前途的药剂来对抗 MTB。结论 本综述旨在激发人们对新的吲哚类药物或治疗结核病的潜在药物的发现和开发的兴趣和努力。现代方法的出现，尤其是那些基于过渡金属催化反应的方法，为吲哚合成领域开辟了巨大的机遇。预期的目标是利用这些现代方法来识别有效和有前途的药剂来对抗 MTB。