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We describe an imidodiphosphorimidate-catalysed asymmetric Wagner–Meerwein shift of aliphatic alkenyl cycloalkanes to cycloalkenes with excellent regio- and enantioselectivity.

A terpene-forming carbocation reaction is described for which a single transition-state structure leads to the formation of many isomeric products via pathways that feature multiple sequential bifurcations. Dynamic effects are shown to contribute to the selectivity of the reaction, with consequences for how enzymes control the biosynthesis of complex natural products.

The Cope rearrangement has been known since the 1940s but, until now, no catalytic asymmetric variant has been reported. Here, a gold(I) catalyst is shown to induce an asymmetric Cope rearrangement of achiral 1,5-dienes containing a cyclopropylidene moiety to produce vinyl cyclopropanes in high yield and good to excellent enantioselectivities.

Bifurcating reaction pathways are those for which a single transition-state structure leads to two separate products, and they have been seen previously in the reactions of certain small molecules. Now, calculations provide evidence for a pathway that bifurcates in the synthesis of a terpene — leading to distinctly different structures.

Preliminary clinical trials suggest that ibogaine and its active metabolite noribogaine have powerful anti-addictive properties, Now, a strategy for the scalable, asymmetric total synthesis of ibogaine has been developed that also provides access to iboga analogues. Biological testing identified a psychoplastogenic iboga analogue that is a potent modulator of the serotonin transporter.

Recently, the pyridoxal-5′-phosphate-dependent enzyme SbzP was reported to catalyse a [3+2]-annulation reaction yielding β-NAD-derived antibiotics. Now, cryo-electron microscopy structures of a stable homologue and computational simulations provide structural and mechanistic insights into this enzymatic reaction.

Selectivity of photochemical reactions is notoriously difficult to model. Now it has been shown that by employing an analogy to ground-state reactions with post-transition-state bifurcations, selectivity for a complex photochemical denitrogenation reaction can be captured and rationalized, and its dynamical origins understood.

Natural products citrinalin B and cyclopiamine B, which contain basic nitrogen atoms that are susceptible to oxidation during synthesis, can be synthesized by the selective introduction and removal of functional groups.

A hydrindanone-based approach to yohimbinoid natural products has been developed. A judicious choice of reaction conditions — inspired by prior work by the Stork group — allows effective control of the stereochemistry at C3 of the yohimbinoid skeleton. This approach has resulted in the first total syntheses of the C3 epimeric natural products venenatine and alstovenine.