Stylissatins B–D, cycloheptapeptides from the marine sponge Stylissa massa
2016
Sun, Jingyuan | Cheng, Wei | de Voogd, Nicole J. | Proksch, Peter | Lin, Wenhan
The NMR and LC–MS guided chromatographic fractionation of the CH2Cl2 extract of the sponge Stylissa massa resulted in the isolation of three new cycloheptapeptides, namely stylissatins B–D (1–3), together with ten known cyclopeptides. The structures of stylissatins B–D were established by comprehensive analysis of 2D NMR (COSY, TOCSY, HMQC, HMBC, and ROESY) in association with the ESI-MS/MS fragmentation. The L-configuration of the amino acid residues was determined based on the Marfey’s method. Stylissatin B (1) exhibited the inhibitory effects against a panel of human tumor cell lines including HCT-116, HepG2, BGC-823, NCI-H1650, A2780, and MCF7 with the IC50 values ranging from 2.4 to 9.8μM.
显示更多 [+] 显示较少 [-]