: Urolithins are microbial metabolites derived from berries and pomegranate fruits, which display anti-inflammatory, anti-oxidative, and anti-aging activities. There are eight natural urolithins (urolithin A-E, M5, M6 and M7), which have been isolated by now. Structurally, urolithins are phenolic compounds and belong to 6H-dibenzo [b,d] pyran-6-one. They have drawn considerable attention because of their vast range of biological activities and health benefits. Recent studies also suggest that they possess anti-SARS-CoV-2 and anticancer effects. In this article, the recent advances in the synthesis of urolithins and their derivatives from 2015 to 2021 are reviewed. To improve or overcome the solubility and metabolism stability issues, the modifications of urolithins are mainly centered on the hydroxy group and lactone group, and some compounds have been found to display promising results and the potential for further study. The possible modes of antitumor action of urolithin are also discussed. Several signaling pathways, including PI3K-Akt, Wnt/β-catenin pathways, and multiple receptors (aryl hydrocarbon receptor, estrogen and androgen receptors) and enzymes (tyrosinase and lactate dehydrogenase) are involved in the antitumor activity of urolithins.

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尿石素及其衍生物的合成及其抗肿瘤作用机制

：尿石素是从浆果和石榴果实中提取的微生物代谢产物，具有抗炎、抗氧化和抗衰老活性。目前已分离出八种天然尿石素（尿石素AE、M5、M6和M7）。在结构上，尿石素是酚类化合物，属于6H-二苯并[b,d]吡喃-6-酮。由于其广泛的生物活性和健康益处，它们引起了相当大的关注。最近的研究还表明它们具有抗 SARS-CoV-2 和抗癌作用。本文综述了2015-2021年尿石素及其衍生物合成的最新进展。为了改善或克服溶解性和代谢稳定性问题，尿石素的修饰主要集中在羟基和内酯基团，并且已经发现一些化合物显示出有希望的结果和进一步研究的潜力。还讨论了尿石素抗肿瘤作用的可能模式。几种信号通路，包括 PI3K-Akt、Wnt/β-catenin 通路和多种受体（芳基烃受体、雌激素和雄激素受体）和酶（酪氨酸酶和乳酸脱氢酶）参与尿石素的抗肿瘤活性。