Viral infections cause many serious human diseases with high mortality rates. New drug‐resistant strains are continually emerging due to the high viral mutation rate, which makes it necessary to develop new antiviral agents. Compounds of plant origin are particularly interesting. The pentacyclic triterpenoids (PTs) are a diverse class of natural products from plants composed of three terpene units. They exhibit antitumor, anti‐inflammatory, and antiviral activities. Oleanolic, betulinic, and ursolic acids are representative PTs widely present in nature with a broad antiviral spectrum. This review focuses on the recent literatures in the antiviral efficacy of this class of phytochemicals and their derivatives. In addition, their modes of action are also summarized.

中文翻译：

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五环三萜及其衍生物的抗病毒活性及其机理研究的最新进展。

病毒感染导致许多严重的人类疾病，死亡率很高。由于高的病毒突变率，新的耐药菌株不断出现，因此有必要开发新的抗病毒药物。植物来源的化合物特别令人感兴趣。五环三萜类化合物（PTs）是一类由三个萜烯单元组成的植物的天然产物。它们具有抗肿瘤，抗炎和抗病毒活性。齐墩果酸，桦木酸和熊果酸是在自然界广泛存在的具有广泛抗病毒谱的代表性PT。这篇综述集中在这类植物化学物质及其衍生物的抗病毒功效的最新文献上。此外，还总结了它们的作用方式。