Extensive chromatographic purification of the chloroform–methanol (1:1) extract of the lichen Parmotrema mesotropum led to the isolation of methyl hematommate (1), methyl-2,4-dihydroxy-3,6-dimethylbenzoate (2), orcinol (3), and atranorin (4). The two major metabolites (1 and 2) were subjected to chemical modification and a total of 15 analogues were synthesized. The synthesized analogues and their parent compounds were evaluated for their anticancer potential against a panel of five human cancer cell lines. Among the tested samples, compound 1g showed potent activity against three cancer cell lines, namely DU145 (IC50 20.07 μM), MCF-7 (IC50 20.94 μM), and U87MG (IC50 25.32 μM). This compound can be considered as lead a molecule for further development.

中文翻译：

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地衣细纹地衣主要代谢物的分离、化学修饰和抗癌活性

对地衣 Parmotrema mesotropum 的氯仿-甲醇 (1:1) 提取物进行广泛的色谱纯化，可分离出血番茄酸甲酯 (1)、2,4-二羟基-3,6-二甲基苯甲酸甲酯 (2)、地衣酚 (3) ) 和 atranorin (4)。对两种主要代谢物（1 和 2）进行化学修饰，共合成了 15 种类似物。对合成的类似物及其母体化合物对一组五种人类癌细胞系的抗癌潜力进行了评估。在测试的样品中，化合物 1g 对三种癌细胞系显示出有效的活性，即 DU145 (IC50 20.07 μM)、MCF-7 (IC50 20.94 μM) 和 U87MG (IC50 25.32 μM)。这种化合物可以被认为是进一步开发的先导分子。