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Chemical investigation of the Australian rainforest plant Doryphora sassafras has resulted in the isolation of a new natural product, 2-methyl-1-(p-methoxybenzyl)-6,7-methylenedioxyisoquinolinium chloride (1). The iodide salt of compound 1 has previously been synthesized but only partially characterized. This paper reports the full spectroscopic characterization of 1 by MS, IR, UV, and NMR data.

The combined CH(2)Cl(2) and MeOH crude extract of a new species of the marine sponge Dysidea, collected in Northern Australia was found to inhibit the binding of [I125] interleukin-8 [IL-8] to the human recombinant IL-8 receptor type A at 500 microg/mL. Bioassay-guided fractionation led to the isolation of three new polyoxygenated sterols 3, 4, and 5. Their structures were assigned on the basis of 1D and 2D NMR experiments, and relative stereochemistries were established by ROESY correlations and analysis of coupling constants. The IC(50) values for inhibition of IL-8Ra for sterols 3, 4, and 5 were 20, 5.5, and 4.5 microM, respectively.

Triunia erythrocarpa was identified as containing alkaloids during chemical screening of Queensland Proteaceae using Dragendorff's reagent. A new tropane, 10-hydroxydarlingine (1), and the known tropane, darlingine (2), were isolated from the leaves of T. erythrocarpa. The absolute stereochemistry of 10-hydroxydarlingine (1) was assigned using the advanced Mosher method. T. erythrocarpa is only the seventh member of the Proteaceae to have been shown to produce alkaloids.

Chemical investigation of the Australian ascidian Pseudodistoma aureum has resulted in the isolation of a new beta-carboline, eudistomin V (1). The known compounds eudistomin H (2) and I (3) were also isolated, and all compounds had their structures determined by spectroscopic means.