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Nowadays asymmetric catalysis is an established re- ality in the organic synthesis community. Nevertheless, the range of applicability both in organic and in organometallic transformations is so large that seeking for new developments seems unstoppable. In this direction, from time to time a new class of “silent” organic compounds rises to prominence and creates new perspectives in the field. Allenyl amides and allenyl ethers are eminent examples of chemical “perturbation” of the current asymmetric synthetic scenario, with recent applications in metal-based and metal-free catalytic enantioselective manip- ulations. Besides their recent rediscovery in an asymmetric and catalytic context, this family of electron-rich allenes has already gained credit in terms of synthetic flexibility and the latest achievements in the field are summarized in this article.

Bicyclic silyl ether derivatives 1, which are derived from simple chemical manipulations of trans-4-L-hydroxyproline, were recently proposed, by us, as conformationally constrained analogues of Jørgensen–Hayashi’s catalysts 2. Despite the structural similarities, 1 displays remarkable performance in iminium chemistry with respect to 2, but much lower reactivity in enamine chemistry. The peculiar structural features of 1 confer a pattern of reactivity between Jørgensen–Hayashi’s catalysts and MacMillan’s imidazolidinones.

SMYD3 is a multifunctional epigenetic enzyme with lysine methyltransferase activity and various interaction partners. It is implicated in the pathophysiology of cancers but with an unclear mechanism. To discover tool compounds for clarifying its biochemistry and potential as a therapeutic target, a set of drug‐like compounds was screened in a biosensor‐based competition assay. Diperodon was identified as an allosteric ligand; its R and S enantiomers were isolated, and their affinities to SMYD3 were determined (K D=42 and 84 μM, respectively). Co‐crystallization revealed that both enantiomers bind to a previously unidentified allosteric site in the C‐terminal protein binding domain, consistent with its weak inhibitory effect. No competition between diperodon and HSP90 (a known SMYD3 interaction partner) was observed although SMYD3–HSP90 binding was confirmed (K D=13 μM). Diperodon clearly represents a novel starting point for the design of tool compounds interacting with a druggable allosteric site, suitable for the exploration of noncatalytic SMYD3 functions and therapeutics with new mechanisms of action., From a distance: SMYD3 lysine methyltransferase is an epigenetic enzyme with multiple cellular functions and the ability to recognize broad range of substrates from histones to cytosolic proteins. An SPR biosensors‐based biophysical strategy for screening SMYD3 ligands was developed and revealed an allosteric binding site. Subsequent crystallographic studies provided a structural description of the novel binding site of SMYD3.

Summary SMYD3 is frequently overexpressed in a wide variety of cancers. Indeed, its inactivation reduces tumor growth in preclinical in vivo animal models. However, extensive characterization in vitro failed to clarify SMYD3 function in cancer cells, although confirming its importance in carcinogenesis. Taking advantage of a SMYD3 mutant variant identified in a high-risk breast cancer family, here we show that SMYD3 phosphorylation by ATM enables the formation of a multiprotein complex including ATM, SMYD3, CHK2, and BRCA2, which is required for the final loading of RAD51 at DNA double-strand break sites and completion of homologous recombination (HR). Remarkably, SMYD3 pharmacological inhibition sensitizes HR-proficient cancer cells to PARP inhibitors, thereby extending the potential of the synthetic lethality approach in human tumors., Graphical Abstract, Highlights • SMYD3 phosphorylation by ATM favors the formation of HR complexes during DSB response • SMYD3 mediates DSB repair by promoting RAD51 recruitment at DNA damage sites • SMYD3 inhibition triggers a compensatory PARP-dependent DNA damage response • Co-targeting SMYD3/PARP leads to synthetic lethality in HR-proficient cancer cells, Molecular Biology; Cell Biology; Cancer

The frequent occurrence of chiral 1-substituted-1,2,3,4-tetrahydroisoquinoline ring systems in a large number of alkaloids, possessing a broad spectrum of biological and pharmaceutical properties, has prompted out a considerable interest in their synthesis. Economical and valuable stereoselective processes based on organocatalytic transformations represent a new avenue for approaching isoquinoline alkaloids with efficiency and creativity.

What do quantum cellular automata (QCA), "on water" reactions, and SN 1-type organocatalytic transformations have in common? The link between these distant arguments is the practical access to useful intermediates and key products through the use of stabilized carbenium ions. Over 10 years, starting with a carbenium ion bearing a ferrocenyl group, to the 1,3-benzodithiolylium carbenium ion, our group has exploited the use of these intermediates in useful and practical synthetic transformations. In particular, we have applied the use of carbenium ions to stereoselective organocatalytic alkylation reactions, showing a possible solution for the "holy grail of organocatalysis". Examples of the use of these quite stabilized intermediates are now also considered in organometallic chemistry. On the other hand, the stable carbenium ions are also applied to tailored molecules adapted to quantum cellular automata, a new possible paradigm for computation. Carbenium ions are not a problem, they can be a/the solution!