作者:Zhi-Yong Zeng、Jin-Xi Liao、Zhen-Ni Hu、De-Yong Liu、Qing-Ju Zhang、Jian-Song Sun
DOI:10.1021/acs.orglett.0c03185
日期:2020.11.6
protocol to construct the challenging glycosidic linkages at C3-OH of C23-oxo oleanane triterpenoids is disclosed, on the basis of which different strategies for the highly efficient synthesis of QS-21 analogues with the west-wing trisaccharide of QS-21 have been established.
A series of N-acyl glucosamine-bearing triterpenoid saponins has been synthesized with cytotoxic activities evaluated against HL-60, PC-3, HCT-116, and CT-26 tumor cells. Saponins incorporated an oleanolic acid (OA) triterpenoidal core exhibited the highest cytotoxic activity. To study the influence of the lengths of acyl-carbon chain on N-position of glucosamine, cells were treated with 28-propargylamides and then reacted with an azidofluorogenic probe under CuAAC click reactions to visualize the intact distributions of these compounds by confocal microscopy and flow cytometry; it was found that cytotoxic-active compounds (30-32) located in the cytosol and inactive compounds bearing longer carbon chains (33-35) were impenetrable across cell membranes. Our study demonstrated the defined lipophilic acyl-carbon chain length can precisely regulate the cytotoxic activity of saponins, which is useful for the future development of cytotoxic agents. Furthermore, using quantitative proteomics and immunolabeling, the mechanism of cytotoxicity induced by the synthetic saponin after membrane penetration could be a result of activation of death receptor pathway and inhibition of PI3K/Akt/mTOR pathway.
Synthesis, antimicrobial and cytotoxic activities, and structure–activity relationships of gypsogenin derivatives against human cancer cells
Using six human cancer celllines in vitro, the cytotoxic activities of all tested compounds were determined by calculating the IC50 values. Doxorubicin and paclitaxel were used as controls. Among the tested compounds, 1a, 1c, and 1d had inhibitory effects with IC50 values of 3.9 μM (HL-60 cells), 5.15 μM (MCF-7 cells), and 5.978 μM (HL-60), respectively. To determine the type of cell death, Hoechst
合成了一系列石膏成分(1)衍生物(1a – i),收率很高,并使用UV,IR,1 H NMR,13 C NMR和LCMS光谱数据建立了衍生物的结构。 在测试的化合物中,1a,1b,1d,1e和gypsogenin(1)对枯草芽孢杆菌和苏云金芽孢杆菌具有抗菌活性,抑制区为10-14 mm。此外,化合物1b,1d和1e对蜡状芽孢杆菌具有抗菌活性,抑制区域为9-14 mm。使用六种体外人类癌细胞系,通过计算IC 50来确定所有被测化合物的细胞毒性活性价值观。阿霉素和紫杉醇用作对照。在测试的化合物中,1a,1c和1d具有抑制作用,IC 50值分别为3.9μM(HL-60细胞),5.15μM(MCF-7细胞)和5.978μM(HL-60)。为了确定细胞死亡的类型,使用了Hoechst 33258(HO)和碘化丙啶(PI)双重染色。尤其是,生ps生成素(1)和化合物1a以20μM的浓度触发了凋亡机制。