Australian Marine and Terrestrial -Derived Surugamides, and Synthetic Analogs, and Their Ability to Inhibit (Heartworm) Motility.

A bioassay-guided chemical investigation of a bacterium, sp. CMB-MRB032, isolated from sheep feces collected near Bathurst, Victoria, Australia, yielded the known polyketide antimycins A4a () and A2a () as potent inhibitors of (heartworm) microfilaria (mf) motility (EC 0.0013-0.

Talarolides Revisited: Cyclic Heptapeptides from an Australian Marine Tunicate-Associated Fungus, sp. CMB-TU011.

Application of a miniaturized 24-well plate system for cultivation profiling (MATRIX) permitted optimization of the cultivation conditions for the marine-derived fungus sp. CMB-TU011, facilitating access to the rare cycloheptapeptide talarolide A () along with three new analogues, B-D (-). Detailed spectroscopic analysis supported by Marfey's analysis methodology was refined to resolve -Me-l-Ala from -Me-d-Ala, l--Ile from l-Ile and l-Leu, and partial and total syntheses of , and permitted unambiguous assignment of structures for (revised) and -.

Glyclauxins A-E: Dimeric Oxaphenalenone Aminoglycosides from an Australian Wasp Nest-Derived Fungus sp. CMB-MW102.

Chemical analysis of cultures of a Queensland mud dauber wasp nest-derived fungus, sp. CMB-MW102, yielded the known dimeric oxaphenalenone duclauxin () along with a family of new 1-deoxy-d-glucosamine adducts, glyclauxins A-E (-). Despite 1D NMR spectra of - being compromised by broadening of selected resonances, structures inclusive of absolute configuration were assigned on the basis of detailed spectroscopic analysis and biogenetic considerations, as well as biomimetic semisynthesis and chemical interconversion.

Phoslactomycins Revisited: Polyketide Tetrahydrofurans and Lactones from an Australian Wasp Nest-Derived sp. CMB-MW079.

Molecular network analysis of sp. CMB-MW079 detected rare phosphorylated natural products. Miniaturized cultivation profiling (MATRIX) established optimal conditions for the production, isolation, and identification of the polyketide δ-lactone phoslactomycin E () and new ester homologues, phoslactomycins J and K ( and ), as well as unprecedented heterocyclic analogues, the tetrahydrofuran cyclolactomycins A-D (-) and γ-lactone isocyclolactomycins A-C (-).

Exploring Natural Product Artifacts: The Polyketide Enterocin Warms to a Ballet of Isomers.

The polyketide enterocin is responsive to environmental stimuli, where mild heating promotes an equilibrium mixture of the isomeric acetals enterocins B and C, which subsequently undergo pseudo-chair-boat inversion to enterocin D. When exposed to aqueous base, enterocin is converted to the isomeric Michael acceptor enterocin F. These studies demonstrate that knowledge of environmental stimuli and associated artifacts is critical to understanding the chemical and ecological properties of enterocins and other classes of natural products.