Haliclonadiamine Derivatives and 6-epi-Monanchorin from the Marine Sponge Halichondria panicea Collected at Iriomote Island
- J Nat Prod. 2016 Apr 22;79(4):1149-54. doi: 10.1021/acs.jnatprod.6b00095.
- 1. Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University , Aoba-ku, Sendai 981-8558, Japan.
- 2. Faculty of Fisheries and Marine Science, Sam Ratulangi University, Kampus Bahu , Manado 95115, Indonesia.
Four new haliclonadiamine analogues, (10Z,12E)-haliclonadiamine (1), (10E,12Z)-haliclonadiamine (2), and halichondriamines A (3) and B (4), were isolated from the Okinawan marine Sponge Halichondria panicea together with haliclonadiamine (5) and papuamine (6). The structures of 1-4 were elucidated on the basis of their spectroscopic data by comparisons with those for 5 and 6. Further separation of the remaining fraction led to the isolation of a new bicyclic guanidine alkaloid, 6-epi-monanchorin (7), along with monanchorin (8). Compound 7 is the epimer of 8 at the 6 position. Compounds 1-6 inhibited the growth of Mycobacterium smegmatis with inhibition zones of 12, 7, 8, 7, 16, and 12 mm at 10 μg/disc, respectively. Compounds 2-4 exhibited weak cytotoxicities against the Huh-7 (hepatoma) human Cancer cell line and were 2-fold less active than 5 and 6. Compounds 7 and 8 were not active against M. smegmatis at 20 μg/disc or the Cancer cell line at 10 μM.