RESUMEN
In order to discover potential antitumor agents from natural products, chemical modifications of ergostane-type triterpenoids from Antrodia camphorata yielded ten new compounds. They include nine C-26 amide derivatives of antcin G (1) and a methyl antcin B (4) derivative with hydroxyamino groups at C-3 and C-7. Chemical structures of the new compounds were elucidated by NMR and MS analyses. Furthermore, cytotoxicities of the triterpenoid derivatives were evaluated using four human cancer cell lines (HL60, U251, SW480, and MCF-7). As a result, 1a, 1g, and 4a exhibited potent cytotoxic activities against HL60, U251, and SW480 with IC50 values of 0.7 ± 0.9, 2.9 ± 1.3, and 2.2 ± 0.6 µM, respectively. Molecular docking indicates that 1a, 1g, and 4a have strong binding affinity with DNA topoisomerase IIα (-9.3, -7.9, and -7.4 kcal/mol, respectively), and that they could be potent topoisomerase IIα inhibitors.
Asunto(s)
Antineoplásicos/farmacología , ADN-Topoisomerasas de Tipo II/metabolismo , Ergosterol/análogos & derivados , Polyporales/química , Inhibidores de Topoisomerasa II/farmacología , Triterpenos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Ergosterol/química , Ergosterol/aislamiento & purificación , Ergosterol/farmacología , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II/química , Inhibidores de Topoisomerasa II/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificaciónRESUMEN
One new meroterpenoid, antroquinonol Y (1), a new ergostane-type sterol, antcamphin Y (2), and a new ergostane-type triterpenoid, antcamphin Z (3), together with 10 known ones (4-13), were isolated from the dish-cultured fungus Antrodia camphorata. Their structures were characterized by extensive NMR and HRESIMS data analyses. The absolute configurations were elucidated by experimental and calculated electronic circular dichroism (ECD) spectral analyses and chemical semi-synthesis. Compounds 1, 3, and 5 exhibited potent inhibitory activities against four human cancer cell lines (U251, HL60, SW480, and A549 cells) with IC50 values of 4.6 to 11.7 µM.