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Zamamiphidins B (

Seven new nitrile-bearing polyacetylenes, named albanitriles A–G, were isolated from a marine sponge of the Mycale genus (Order: Poecilosclerida, Family: Mycalidae) collected near Albany, Western Australia. Structural elucidation was achieved using a combination of high-resolution mass spectrometry and ultraviolet/visible, infrared, and nuclear magnetic resonance spectroscopy. The compounds were found to possess moderate activity against Giardia duodenalis when compared to a metronidazole positive control.

Two previously reported bis-indole alkaloids, echinosulfone A and echinosulfonic acid B, have been isolated for the first time from a Western Australian marine sponge, Crella sp. (order: Poecilosclerida, family: Crellidae). Single-crystal X-ray diffraction of a decomposition product of echinosulfone A prompted our investigation and subsequent structure reassignment of the echinosulfonic acid natural product family, which we report here. The reassignments are supported by analysis of 1D and 2D NMR data, MS fragmentation, and DFT calculations of 13C NMR shifts.

Seven new nitrile-bearing polyacetylenes, named albanitriles A-G, were isolated from a marine sponge of the

A new manzamine alkaloid, zamamidine D (1), was isolated from an Okinawan Amphimedon sp. marine sponge. The structure of zamamidine D (1) including the relative configuration was elucidated on the basis of spectroscopic data. Zamamidine D (1) is the first manzamine alkaloid possessing a 2,2′-methylenebistryptamine unit as the aromatic moiety instead of a β-carboline unit. Zamamidine D (1) showed antimicrobial activity against several bacteria and fungi.

The isolation of bromotyrosine alkaloids, some of which are enantiomers of previously isolated compounds, has highlighted a possible enantiodivergence in their biosynthesis. Two new (1, 2) and six known bromotyrosine alkaloids (4–9), and the enantiomer (10) of a known compound, have been isolated from a Western Australian marine sponge, Pseudoceratina cf. verrucosa. The compounds inhibited the growth of multidrug-resistant and methicillin-resistant Staphylococcus aureus with comparable activity to vancomycin. In addition, one possible artifact of extraction (3) containing an ethoxy group was isolated. From analysis of the known bromotyrosine alkaloids, a biogenesis is proposed that explains the formation of antipodal natural products within this family of sponges.

A new dimeric sesquiterpenoid with eudesmane and aromadendrane skeletons linked through a urea fragment, halichonadin E ( 1), was isolated from a marine sponge Halichondria sp., and the gross structure and relative configuration of 1 were elucidated on the basis of spectroscopic data. Halichonadin E ( 1) is the first hetero-dimeric sesquiterpenoid with eudesmane and aromadendrane skeletons linked through a urea fragment.

Nine new sesquiterpenoid quinones, nakijiquinones J-R (1-9), have been isolated from three collections of Okinawan marine sponges of the family Spongiidae, and the structures and configurations were elucidated from the spectroscopic data and chemical correlations. Nakijiquinones J-L (1-3), M and N (4 and 5, respectively), O (6), P and Q (7 and 8, respectively), and R (9) are new sesquiterpenoid quinones possessing (S)-2-methylbutylamine, isopentylamine, isobutylamine, phenethylamine, and taurine residues, respectively, attached to each quinone ring.

Four new bromopyrrole alkaloids, nagelamides O (1) and P (2) and mukanadins E (3) and F (4), were isolated from three collections of Okinawan marine sponges of the genus Agelas. The structures and stereochemistry of 1−4 were elucidated on the basis of their spectroscopic data.

A new sesquiterpenoid with an aromadendrane skeleton, halichonadin F (1), and the Cu(I) complex of haliconadin C (2) were isolated from a marine sponge Halichondria sp., and the structures and relative stereochemistries of 1 and the complex of 2 were elucidated on the basis of spectroscopic data and chemical methods.

A unique C2-symmetrical 4,4'-bis(7-hydroxy)indole alkaloid, dendridine A (1), was isolated from an Okinawan marine sponge Dictyodendrilla sp., and the structure was elucidated by spectroscopic data. Dendridine A (1) exhibited antibacterial and antifungal activities.

A new beta-carboline alkaloid with an imidazole ring, gesashidine A (1), has been isolated from an Okinawan marine sponge of the family Thorectidae (SS-1035), and the structure was elucidated from the spectroscopic data.

Eight new dimeric bromopyrrole alkaloids, nagelamides A-H (1-8) and a monomeric one, 9,10-dihydrokeramadine (9), have been isolated from the Okinawan marine sponge Agelas sp., and the structures were elucidated from spectroscopic data. Nagelamides A-H (1-8) exhibited antibacterial activity against Gram-positive bacteria. Nagelamide G (7) inhibited protein phosphatase 2A activity.

A new bromotyrosine alkaloid, nakirodin A (1), has been isolated from an Okinawan marine Verongid sponge. The structure was elucidated on the basis of spectroscopic data.

Two new sesterterpenoids, luffariolides H (1) and J (2), have been isolated from an Okinawan marine sponge Luffariella sp. The structures of 1 and 2 were elucidated on the basis of spectroscopic data.

A new cytotoxic bis-indole alkaloid, hyrtinadine A (1), with a pyrimidine moiety has been isolated from an Okinawan marine sponge Hyrtios sp., and the structure was elucidated on the basis of spectroscopic data.