Nematocidal thiocyanatins from a southern Australian marine sponge Oceanapia sp.

Investigations of a southern Australian marine sponge, Oceanapia sp., have yielded two new beta methyl branched bisthiocyanates, thiocyanatins D1 (3a) and D(2) (3b), along with two new thiocarbamate thiocyanates, thiocyanatins E1 (4a) and E2 (4b). The new thiocyanatins belong to a rare class of bioactive marine metabolite previously only represented by thiocyanatins A-C (1, 2a/b).

Esmodil: an acetylcholine mimetic resurfaces in a Southern Australian marine sponge Raspailia (Raspailia) sp.

Bioassay directed fractionation of a Raspailia (Raspailia) sp. (Order Poecilosclerida; Family Raspailiidae) collected during scientific trawling operations off the Northern Rottnest Shelf yielded as nematocidal agents the known metabolites, phorboxazoles A (1) and B (2). Further examination revealed the new natural product but known synthetic compound, esmodil (3).

Aspergillicins A-E: five novel depsipeptides from the marine-derived fungus Aspergillus carneus.

A search for new antiparasitic agents from a strain of the fungus Aspergillus carneus isolated from an estuarine sediment collected in Tasmania, Australia, yielded the known terrestrial fungal metabolite marcfortine A (1) as an exceptionally potent antiparasitic agent. This study also yielded a series of new depsipeptides, aspergillicins A-E (2-6) and the known terrestrial fungal metabolite acyl aszonalenin (7). Marcfortine A (1) and acyl aszonalenin (7) were identified by spectroscopic analysis, with comparison to literature data.

Convolutindole A and convolutamine H, new nematocidal brominated alkaloids from the marine bryozoan Amathia convoluta.

Nematocidal activity of an extract of the marine bryozoan Amathia convoluta, collected from Tasmania's east coast, was ascribed to two novel tribrominated alkaloids: convolutamine H (2) and convolutindole A (5), an indole possessing the unusual N-methoxy moiety. The structures were established by spectroscopic techniques.

Equilibrating isomers: bromoindoles and a seco-xanthine encountered during a study of nematocides from the southern Australian marine sponge Hymeniacidon sp.

Bioassay-directed fractionation of a Hymeniacidon sp. yielded as nematocidal agents the equilibrating E/Z bromoindole ethyl esters 1 and 2 and corresponding methyl esters 3 and 4. Also isolated for the first time as a natural product was an equilibrating mixture of seco-xanthine formamides, attributed the trivial name hymeniacidin (5).

Phoriospongin A and B: two new nematocidal depsipeptides from the Australian marine sponges Phoriospongia sp. and Callyspongia bilamellata.

Bioassay-directed fractionation of two southern Australian sponges, Phoriospongia sp. and Callyspongia bilamellata, yielded two new nematocidal depsipeptides, identified as phoriospongins A (1) and B (2). The structures of the phoriospongins were determined by detailed spectroscopic analysis and comparison with the previously reported sponge depsipeptide cyclolithistide A (3), as well as ESIMS and HPLC analysis of acid hydrolysates.