The fundamental role played by actin in the regulation of eukaryotic cell maintenance and motility renders it a primary target for small-molecule intervention. In this arena, a class of potent cytotoxic cyclodepsipeptide natural products has emerged over the last quarter-century to stimulate the fields of biology and chemistry with their unique actin-stabilizing properties and complex peptide-polyketide hybrid structures. Despite considerable research effort, a structural basis for the activity of these secondary metabolites remains elusive, not least for the lack of high-resolution structural data and a reliable synthetic route to diverse compound libraries. In response to this, an efficient solid-phase approach has been developed and successfully applied to the total synthesis of jasplakinolide and chondramide C and diverse analogues. The key macrocylization step was realized using ruthenium-catalyzed ring-closing metathesis (RCM) that in the course of a library synthesis produced discernible trends in metathesis reactivity and E/Z-selectivity. After optimization, the RCM step could be operated under mild conditions, a result that promises to facilitate the synthesis of more extensive analogue libraries for structure-function studies. The growth inhibitory effects of the synthesized compounds were quantified and structure-activity correlations established which appear to be in good alignment with relevant biological data from natural products. In this way a number of potent unnatural and simplified analogues have been found. Furthermore, potentially important stereochemical and structural components of a common pharmacophore have been identified and rationalized using molecular modeling. These data will guide in-depth mode-of-action studies, especially into the relationship between the cytotoxicity of these compounds and their actin-perturbing properties, and should inform the future design of simplified and functionalized actin stabilizers as well.

Shaping of otherwise powdery metal-organic frameworks is recognized as a more-and-more important issue to advance them to the application stage. Monolithic MOF composites were synthesized using micro-to-mesoporous MIL-100(Fe,Cr) and MIL-101(Cr) as thermally and chemically stable MOFs together with a mesoporous resorcinol-formaldehyde based xerogel as binding agent. The monolithic bodies could be loaded with up to 77 wt% of powdery MIL material under retention of the MIL surface area and porosities (from N 2 adsorption) by prepolymerization of the xerogel solution. The obtained monoliths are mechanically stable and adsorb close to the expected water vapor amount according to the MIL weight percentage.There is no loss of BET surface area, porosity and water uptake capacity especially for the MIL-101(Cr) composites. Water vapor adsorption isotherms show that the 77 wt% MIL-101(Cr) loaded composite even features a slightly increased water vapor uptake compared to pure MIL-101(Cr) up to a relative vapor pressure of P·P 0 -1 = 0.5. These hydrophilic monolithic composites could be applied for heat transformation application such as thermally driven adsorption chillers or adsorption heat pumps.

Over the past decade, asymmetric aminocatalysis has become a reliable synthetic platform for generating stereogenic centres at the α and β positions of unmodified carbonyl compounds with very high fidelity. More recently, chemists have become interested in using aminocatalysis for targeting stereocentres even more remote from the catalyst's point of action. The key to success is the ability of the amine catalyst to propagate the electronic effects inherent to aminocatalytic reactivity modes (i.e. the HOMO-raising and the LUMO-lowering activating effects) through the conjugated π-system of poly-unsaturated carbonyls while transmitting the stereochemical information at distant positions. This feature article outlines how the combination of aminocatalysis with the principle of vinylogy has brought about the development of dienamine, trienamine, and vinylogous iminium ion activations, novel strategies for the asymmetric functionalisation of carbonyl compounds at their γ-, ε-, and δ-positions, respectively.

Actin glue: An E‐selective ring‐closing metathesis as the key step allowed the solid‐phase‐based total synthesis of the F‐actin stabilizer chondramide C as well as the establishment of its hitherto unknown stereochemistry. A strong influence of the polyketide configuration was revealed in cellular assays. Docking studies on the F‐actin filament structure led to a detailed model of the binding site.

The synthesis of a focused library of jasplakinolide analogs with a 1,2,3-triazole in place of an E-configured double bond is described, featuring the Cu(I) catalyzed azide-alkyne cycloaddition reaction as an efficient macrocyclization tool.

Enantioselective hydrogenation of furans and benzofurans remains a challenging task. We report the hydrogenation of 2- and 3-substituted furans by using iridium catalysts that bear bicyclic pyridine-phosphinite ligands. Excellent enantioselectivities and high conversions were obtained for monosubstituted furans with a 3-alkyl or 3-aryl group. Furans substituted at the 2-position and 2,4-disubstituted furans proved to be more difficult substrates. The best results (80-97% conversion, 65-82% enantiomeric excess) were obtained with monosubstituted 2-alkylfurans and 2-[4-(trifluoromethyl)phenyl]furan. Benzofurans with an alkyl substituent at the 2- or 3-position also gave high conversions and enantioselectivity, whereas 2-aryl derivatives showed essentially no reactivity. The asymmetric hydrogenation of a 3-methylbenzofuran derivative was used as a key step in the formal total synthesis of the cytotoxic naphthoquinone natural product (-)-thespesone.

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The study of classical ring-closing metathesis and relay ring-closing metathesis in a total synthesis of Jasplakinolide and its desbromo analog is described.