European Journal of Organic Chemistry

Metallofoldamers are peptidomimetic and abiotic oligomers that fold in a controlled manner upon binding to metal ions. This microreview describes metal coordination in abiotic, single-stranded, linear or cyclic oligomers, which may nucleate the formation of chiral helical structures, enhance an existing secondary structure, or enable the formation of functional materials.

The total synthesis of 2 plant-derived inhibitors of the NF-κB signaling pathway is described. A key step in the efficient reaction sequence is a late-stage oxidative cleavage reaction that was carried out in the absence of protecting groups to give the natural products directly. Biological studies on synthetic material confirmed that these compounds act late in the NF-κB signaling pathway.

Highly lipophilic dipeptide building blocks were synthesized from totally unprotected enantiopure α-trifluoromethyl α-amino acids. The synthesis of a tripeptide through a coupling reaction at the deactivated N-terminal position was achieved.

Doubly fused metalloporphyrins have been obtained in a few simple steps and the electronic properties of these new compounds studied by electrochemistry. The X-ray structure of the free base is reported.

Isolation of two truncated tricyclic intermediates from the ERG7^Y99X site-saturated mutants suggests its functional role in affecting both chair–boat 6–6–5 tricyclicMarkovnikov C-14 cation stabilization and the stereochemistry of the protons at the C-15 position for subsequent deprotonation.

An unprecedented approach to the single-step synthesis of 3,4-fused pyrimidin-2-one and pyrimidin-2-thione derivatives by a three-component coupling reaction from an α-acidic imine compound, a nitrile, andtriphosgene or carbon disulfide is described. This method presents a variety of pyrimidines from commercially available reagents.

A new methodology is described for the synthesis of glycosyl amino acids from unprotected sugars by traceless Staudinger ligation.

Azepinoindole alkaloid, (±)-aurantioclavine, was synthesized from Nb-benzylserotonin and 3-methylbut-2-enal in three steps.A base-promoted Pictet–Spengler reaction was the key step.

A solid-state, chiral, helical, columnar, organic fluorophore having a π-conjugated phenylene ethynylene unit was prepared by using 4-[2-(4-methylphenyl)ethynyl]benzoic acid and 1-phenylethylamine. Such a chiralπ-conjugated organic fluorophore can be obtained from achiral and racemic component molecules, and it exhibits circularly polarized luminescence (CPL) in the solid state.

The triazoloquinoline–pyridine system undergoes ring-chain isomerisation to afford two different structures depending on theelectronic and steric properties of substituents R.

In order to clearly show the influence ofπ-π interactions between the conjugatedsystem and the fullerene moiety on the electronic properties of C₆₀-(π-conjugated oligomer) conjugates, macrocyclic dyads in which the two components are at the van der Waals contact have been prepared and their properties investigated.

A catalysed intramolecular cyclisation of alcohols on nonactivated olefins was achieved with 5 mol-% of aluminiumtriflate.

The catalytic properties of a family of chiral polystyrene-supported monodentate ligands have been studied in rhodium-catalysed asymmetric hydrogenation and palladium-catalysed asymmetric allylic alkylation. Additionally, the supported ligands were applied in the heteroligand approach by combining them with nonsupported monodentate ligands.

The asymmetric allylic amination ofMorita–Baylis–Hillman carbonates with cyclic imides catalysed by a modified cinchona alkaloid (DHQD)₂PYR has been developed. An array of α-methylene β-amino esters were obtained with good-to-excellent enantioselectivities (up to 94 % ee) and in high yields (up to 97 %).

Barbatines A–D (1–4) have been isolated from whole plants of Scutellaria barbata along with the known scutebarbatine A (5). Compounds 1–4 have a neo-clerodane diterpenoid skeleton with a (15→16) lactone moiety, but 1 and 2 differ from 3 and 4 by an inversion of the chiral center C-13. Compounds 1 and 5 showed good protection of cells against H₂O₂ with ED₅₀ values of 16.8 and 5.0 μM, respectively.

Deoxygenated carbohydrate analogues with pyran structure and a perfluoroalkyl group in position 4 have been synthesized in three steps from easily available enol ethers that are also homoallylic alcohols and contain an α acetal moiety next to the carbon–carbon double bond.

An effective and “green chemistry” approach to the synthesis of α-aryl α-oxoheterocyclic ketene N,N-acetals containing an electron-rich aromatic ring was developed electrochemically. In addition, density functional theory calculations were performed to explain the exclusive formation of α-carbon-arylated products.

Taurine and structurally diverse substituted taurines have been synthesized starting from vicinal amino alcohols or aziridines and carbon disulfide with peroxyformic acid oxidation of the thiazolidine-2-thione intermediates the key step. The method is a salt-free and versatile route.

4H-Quinolizine derivatives were prepared, under mild conditions, from sulfonyl ketene dithioacetals (1a,b). The reaction involved replacement of the remaining methylsulfanyl group with a proton after the ring-closure reaction; metallic reagents were not used along the reaction pathway. The synthesized 4H-quinolizines exhibited strong fluorescence in the solid state.

A variety of chlorinated arenes were prepared by one-pot cyclizations of the first reported 4-chloro-1,3-bis(trimethylsilyloxy)buta-1,3-dienes with a variety of 1,3-dielectrophiles.