New diterpene alkaloids from the marine sponge Agelas mauritiana. Issue 39 (3rd May 2017) - Hong, Li-Li
Abstract : Chemical investigation of the sponge Agelas mauritiana led to the isolation of five new diterpene alkaloids and two known compounds, in which (+)-agelasine B (2 ) and agelasine D (7 ) showed potent antibacterial activity. Abstract : Chemical investigation of an ethanol extract of the sponge Agelas mauritiana led to the isolation and characterization of five new diterpene alkaloids, namely, (−)-8′-oxo-agelasine B (1 ), (+)-agelasine B (2 ), (+)-8′-oxo-agelasine C (3 ), agelasine V (4 ), and (+)-8′-oxo-agelasine E (5 ), along with two known compounds, (−)-8′-oxo-agelasine D (6 ), and agelasine D (7 ). The structures of these compounds were determined by interpretation of spectroscopic data and comparison with literature properties. Compounds1 and3–5 are the second example of 8′-oxo-agelasine analogs. Compounds2 and7 not only exhibited moderate cytotoxicity toward the cancer cell lines PC9, A549, HepG2, MCF-7, and U937 with IC50 values of 4.49–14.41 μM, but also showed potent antibacterial activities against a panel of methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates with MIC90 values of 1–8 μg mL −1 .