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Funder: Woolf Fisher, Funder: Trinity Hall, The marine natural product hemicalide displays potent anticancer activity. While detailed NMR experiments established the planar carbon skeleton, its full configurational assignment proved enigmatic. This Review summarises ongoing synthetic efforts and NMR studies on hemicalide, which have succeeded in reducing the number of possible stereoisomers from more than one million to a more manageable eight structures, setting the stage for a focused total synthesis campaign.

The intention of this study was to provide a detailed analysis, undertaken at the personal level, of the phenomenon of rural retreating. The personal approach was adopted as the only way of documenting the lifestyles and land use of the new settlers. The Cygnet-Channel area was chosen for study, as it was felt that a relatively comprehensive survey of the area could be completed within the time-scope of the course. To have taken a larger area would have meant a less satisfactory coverage and would have limited the depth of information collected. As such, the study would have been like many others, and would not have come to grips with the phenomenon of rural retreating on the personal level. A further intention of this report was to devise a workable terminology and classification. To this end, the reader is provided with a glossary of terms used in the report, thus avoiding the ambiguity of many of the popular terms. The typology of landholders is presented as a system which makes the categorisation measurable and avoids the value judgements on lifestyles which commonly distort the assessment of effective differences between landholders. The identification of areas of concern and potential problems, stemming from the inward migration of previously urban-based people, was the goal of this report. The discussion of these issues leads to the question of what action can be taken and by whom? The strategies presented do not attempt to resolve these questions; rather the intention is to indicate a few directions and alternatives for the future.

Microtubules are dynamic cytoskeletal polymers that spontaneously switch between phases of\ud growth and shrinkage. The probability of transitioning from growth to shrinkage, termed\ud catastrophe, increases with microtubule age, but the underlying mechanisms are poorly\ud understood. Here, we set out to test whether microtubule lattice defects formed during\ud polymerization can affect growth at the plus end. To generate microtubules with lattice defects,\ud we used microtubule-stabilizing agents that promote formation of polymers with different\ud protofilament numbers. By employing different agents during nucleation of stable microtubule\ud seeds and subsequent polymerization phase, we could reproducibly induce switches in\ud protofilament number and induce stable lattice defects. Such drug-induced defects led to frequent\ud catastrophes, which were not observed when microtubules were grown in the same conditions but\ud without a protofilament number mismatch. Microtubule severing at the site of the defect was\ud sufficient to suppress catastrophes. We conclude that structural defects within microtubule lattice\ud can exert effects that can propagate over long distances and affect the dynamic state of the\ud microtubule end.

The diverse and complex structures of polyketide natural products have stimulated the imagination of synthetic chemists for decades. Captivated by their often impressive biological activities and their dazzling array of stereochemically-rich motifs, we have been motivated to achieve their efficient and stereocontrolled total synthesis. This review captures snapshots from our thirty-year foray into the total synthesis of 18 polyketide natural products, detailing the unique challenges, discoveries and revelations made en route prior to eventual success. Notably, crucial to each of these campaigns was the judicious application of highly selective aldol reactions to iteratively configure the densely oxygenated stereoclusters that characterise this fascinating class of bioactive natural products.