Department of Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes Str. 2, D-06120 Halle (Saale), Germany.
Molecules. 2022 Mar 29;27(7):2220. doi: 10.3390/molecules27072220.
Pentacyclic triterpenoic acids (betulinic, oleanolic, ursolic, and platanic acid) were selected and subjected to acetylation followed by the formation of amides derived from either piperazine or homopiperazine. These amides were coupled with either rhodamine B or rhodamine 101. All of these compounds were screened for their cytotoxic activity in SRB assays. As a result, the cytotoxicity of the parent acids was low but increased slightly upon their acetylation while a significant increase in cytotoxicity was observed for piperazinyl and homopiperazinyl amides. A tremendous improvement in cytotoxicity was observed; however, for the rhodamine B and rhodamine 101 conjugates, and compound , an ursolic acid derived homopiperazinyl amide holding a rhodamine 101 residue showed an EC = 0.05 µM for A2780 ovarian cancer cells while being less cytotoxic for non-malignant fibroblasts. To date, the rhodamine 101 derivatives presented here are the first examples of triterpene derivatives holding a rhodamine residue different from rhodamine B.
五环三萜酸（白桦脂酸、齐墩果酸、熊果酸和角鲨烯酸）被选择并进行乙酰化，然后形成哌嗪或高哌嗪衍生的酰胺。这些酰胺与若丹明 B 或罗丹明 101 偶联。所有这些化合物都在 SRB 测定中进行了细胞毒性筛选。结果表明，母体酸的细胞毒性较低，但乙酰化后略有增加，而哌嗪基和高哌嗪基酰胺的细胞毒性显著增加。然而，对于若丹明 B 和罗丹明 101 缀合物以及化合物 ，一种具有罗丹明 101 残基的熊果酸衍生的高哌嗪基酰胺对 A2780 卵巢癌细胞的 EC = 0.05 µM，而对非恶性成纤维细胞的细胞毒性较小。迄今为止，本文所呈现的罗丹明 101 衍生物是首例具有不同于若丹明 B 的罗丹明残基的三萜衍生物。
