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The global COVID-19 pandemic has claimed the lives of millions and disrupted nearly every aspect of human society. Currently, vaccines remain the only widely available medical means to address the cause of the pandemic, the SARS-CoV-2 virus. Unfortunately, current scientific consensus deems the emergence of vaccine-resistant SARS-CoV-2 variants highly likely. In this context, the design and development of broad-spectrum, small-molecule based antiviral drugs has been described as a potentially effective, alternative medical strategy to address circulating and re-emerging CoVs. Small molecules are well-suited to target the least-rapidly evolving structures within CoVs such as highly conserved RNA replication enzymes, and this renders them less vulnerable to evolved drug resistance. Examination of the vast literature describing the inhibition of RNA viruses by Amaryllidaceae alkaloids suggests that future, broad-spectrum anti-CoV drugs may be derived from this family of natural products.

A simple radical-based route to gem-α-dichloroketones, relying on the degenerative addition transfer of (S)-[3,3-dichloro-2-oxopropyl]-O-ethyl dithiocarbonate (xanthate), is described. The adducts can then be converted into Z-enoates by exposure to Et3N in methanol. In the case of certain substrates, it was possible to form skipped dienoic acid and methyl E,E-dienoates.

RANEY® cobalt, which was first prepared in the 1930s, is known to function effectively as a catalyst for certain chemoselective reductions. However, its utility in chemical synthesis does not seem to have been fully appreciated. This first comprehensive survey of the literature on chemical transformations involving RANEY® cobalt attempts to redress matters by, among other things, highlighting the differences between the performance of this system and its much more well-known but usually less selective congener RANEY® nickel. A reliable method for preparing consistently effective RANEY® cobalt is presented together with a protocol that avoids the need to use it with high pressures of dihydrogen. As such, it is hoped more attention will now be accorded to the title reagent that offers considerable promise as a powerful tool for chemical synthesis, particularly in the assembly of polycyclic frameworks through tandem reductive cyclisation processes.

We thank the Australian Research Council and the Institute of Advanced Studies for generous financial support.

The epoxyquinol natural product (+)-isoepiepoformin (1) has been synthesized for the first time and in an unambiguous fashion by using the scalemic cis-1,2-dihydrocatechol 2 as starting material. The spectroscopic data derived from the synthetic sample of compound 1 match those reported in the literature for the natural product and thereby confirm the structure assigned to the latter.