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Phosphatidylcholine (PC) is the most abundant phospholipid in eukaryotic cell membranes. In eukaryotes, two highly homologous enzymes, cholinephosphotransferase-1 (CHPT1) and choline/ethanolamine phosphotransferase-1 (CEPT1) catalyze the final step of de novo PC synthesis. CHPT1/CEPT1 joins two substrates, cytidine diphosphate-choline (CDP-choline) and diacylglycerol (DAG), to produce PC, and Mg2+ is required for the reaction. However, mechanisms of substrate recognition and catalysis remain unresolved. Here we report structures of a CHPT1 from Xenopus laevis (xlCHPT1) determined by cryo-electron microscopy to an overall resolution of ~3.2 Å. xlCHPT1 forms a homodimer, and each protomer has 10 transmembrane helices (TMs). The first 6 TMs carve out a cone-shaped enclosure in the membrane in which the catalysis occurs. The enclosure opens to the cytosolic side, where a CDP-choline and two Mg2+ are coordinated. The structures identify a catalytic site unique to eukaryotic CHPT1/CEPT1 and suggest an entryway for DAG. The structures also reveal an internal pseudo two-fold symmetry between TM3-6 and TM7-10, and suggest that CHPT1/CEPT1 may have evolved from their distant prokaryotic ancestors through gene duplication. CDP-alcohol phosphatidyltransferase (CDP-AP) is a family of membrane-embedded enzymes that synthesize phospholipids. The authors report structural and functional studies of a eukaryotic CDP-AP and reveal a catalytic center and structural fold different from these of prokaryotic homologs. [ABSTRACT FROM AUTHOR]

An organocatalyzed asymmetric dearomative [3+2] annulation reaction of electron‐deficient 2‐nitrobenzo heteroarenes including 2‐nitrobenzofurans, 2‐nitrobenzothiophenes and 2‐nitroindoles with 3‐isothiocyanato oxindoles was developed. With a multiple hydrogen‐bonding bifunctional thiourea as the catalyst, the reaction displays broad substrate scope and provides an access to structurally diverse polycyclic spirooxindoles containing three contiguous stereogenic centers in high yields with good diastereo‐ and enantioselectivities (up to 99% yield, 94:6 dr, and 97% ee). This organocatalysis protocol is able to afford the products with complementarily diastereoselectivity versus the previous work with transition metal catalysis. [ABSTRACT FROM AUTHOR]

In this study, a radical‐triggered cyclization of o‐alkenyl aromatic isocyanides prepared from accessible starting materials is developed. The reaction provides a general and efficient method for the synthesis of 4‐CN‐2‐CF3/CF2H‐containing quinolines under copper or visible‐light photoredox catalysis in a one‐pot synthetic procedure. This protocol demonstrates good to high yields, broad substrate scope, and good functional group tolerance. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed remote meta‐selective C‐H functionalization of arylacetic acid has been developed using a pyrimidine template. This transformation is not only tolerated to a diverse range of arylacetic acid and alkene substrates but also applicable to the synthesis of pharmaceutically active ibuprofen derivatives. Moreover, the pyrimidine template was readily removable and recyclable under mild conditions. [ABSTRACT FROM AUTHOR]

A metal-organic framework-based composite with reduced graphene oxide was successfully designed, prepared and used for the first time as a support for Pd nanoparticles. The as-synthesized UiO66@RGO-Pd composite was characterized by powder X-ray diffraction (XRD), thermal gravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption. The reduction of nitro compounds was used to demonstrate the catalytic efficiency, which showed excellent activity due to the large surface area and well-defined pore structure. Additionally, the Pd NPs confined in mesoporous cages could be readily recovered after simple filtration and reused for at least six consecutive cycles without loss of activity. [ABSTRACT FROM AUTHOR]

: A crystal structure of a member of the UbiA family of membrane-embedded prenyltransferases reveals the architecture of the active site and suggests a possible mechanism for catalysis. [ABSTRACT FROM AUTHOR]

Histone acetyltransferase 1 is the founding member of the histone acetyltransferase superfamily and catalyzes lysine acetylation of newly synthesized histone H4. Here we report a 1.9-A resolution crystal structure of human histone acetyltransferase 1 in complex with acetyl coenzyme A and histone H4 peptide. The crystal structure reveals that the cofactor and the side chain of lysine 12 of histone H4 peptide are placed in the canyon between the central and C-terminal domains. Histone H4 peptide adopts a well-defined conformation and establishes an extensive set of interactions with the enzyme including invariant residues Glu64 and Trp199, which together govern substrate-binding specificity of histone acetyltransferase 1. Our structure-guided enzyme kinetic study further demonstrates a cumulative effect of the active-site residues Glu187, Glu276, and Asp277 on deprotonation of the e-amino group of reactive Lys12 for direct attack of the acetyl group of the cofactor. [ABSTRACT FROM AUTHOR]

Abstract: Equimolar reactions of the derivatives of ((2-hydroxynapthalen-1-yl)methylene)aniline with methyltrioxorhenium (MTO) lead to complexes 1–4, where MTO is coordinated via the oxygen of the former hydroxyl-group to MTO. The resulting complexes are very stable but not particularly catalytically active if no electron acceptor resides on the Schiff base. The electron withdrawing groups placed on the Schiff base ligand have the effect of increasing the catalytic activity but somewhat decrease the complex stability. [Copyright &y& Elsevier]

Abstract: A (salicylidene)aniline derived Schiff-base adduct of methyltrioxorhenium(VII), displaying both a cis- and a trans-arrangement of the Schiff-base ligand to the Re bound methyl group has been synthesized and described. Despite displaying some significant differences in the solid state (e.g. Re–O (Schiff base) bond distance, Re–C bond distance and several bond angles), the two configurations are indistinguishable in solution, obviously interchanging quickly. [Copyright &y& Elsevier]

Abstract: The transformation of acetonides into the corresponding diacetates is often required in the synthetic chemistry. An efficient procedure for direct conversion of acetonides into diacetates in the presence of Bi(OTf)3·xH2O under mild conditions has been developed. Primary hydroxyl-acetonides could be selectively transformed into diacetates in the presence of anomeric acetonides and the anomeric acetonides could be tunably converted into 2-acetoxyisopropyl or diacetate groups. [Copyright &y& Elsevier]

Unveils the Escherichia coli TAG glycosylase as an unexpected addition to the multi-faceted family of helix-hairpin-helix (HhH) DNA glycosylases. Helical domains of the three-dimensional structural cores of HhH DNA glycosylases; Coupling substrate specificity to catalysis.

For the first time, a strategy for the enantioselective Rh-TaniaPhos catalyzed asymmetric hydrogenation of unprotected β-enamine phosphonates directly to free β-amino phosphonates is reported which occurs with high yields and good enantioselectivities (up to 86% ee). [ABSTRACT FROM AUTHOR]

The Front Cover shows a polymer tube containing a continuous flow of plug reactors used for the synthesis of colloidal metal nanocrystals. In their Full Paper, Wang et al. report how such plug reactors can be applied to the continuous and scalable production of palladium icosahedral nanocrystals with uniform and controllable sizes. More information can be found in the Full Paper by Wang et al. on page 1658 in Issue 9, 2016 (DOI: 10.1002/cctc.201600060). [ABSTRACT FROM AUTHOR]

The products are obtained in very high yields and with high (alkyl) or excellent (aryl and hetaryl substituted derivatives) enantiomeric excesses. [ABSTRACT FROM AUTHOR]

The title transformation provides straightforward synthetic access to an indenoazepine skeleton through a sequence which includes the formation of a rhodium(III) azavinyl carbene, dual C(sp2)-H functionalization, and [3 + 2]/[5 + 2] annulation. [ABSTRACT FROM AUTHOR]

Mild conditions, broad substrate scope, and the commercially available Rh-DuanPhos catalyst are features of this hydrogenation. [ABSTRACT FROM AUTHOR]

The article presents chemical reactions related to the research " Alkylation of Terminal Alkynes with Transient σ-Alkylpalladium(II) Complexes: A Carboalkynylation Route to Alkyl-Substituted Alkynes" by R.-J. Song and others published in "Chemistry - A European Journal" in 2014.

A novel method for the synthesis of 2,3-dihydro-1H-azepines is established using a silver-catalyzed [5 + 2] cycloaddition of γ-aminoketones with terminal alkynes. [ABSTRACT FROM AUTHOR]

Abstract: Ni nanoparticles were loaded on TiO2 nanotube arrays (Ni/TiO2NTs) via pulsed electrodeposition method and employed as catalyst for methanol oxidation in alkaline media. The as-prepared Ni/TiO2NTs catalyst was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical analyzer. The electrochemical studies showed that Ni/TiO2NTs under illumination exhibited higher catalytic activity and stronger poisoning-tolerance for methanol oxidation than that in the dark. The effect of illumination which improved catalytic activity of Ni/TiO2NTs were attributed to the p–n junction formed at the interface between Ni(OH)2 and TiO2NTs resulting in the photo-generated holes flow into Ni(OH)2, thus, the transmitted holes boosted the oxidation of Ni(OH)2 and produced the OHze methanol and intermediates that absorbed on the catalyst. The present study shows Ni/TiO2NTs can act as a promising candidate for the anode catalyst in photo assist direct methanol fuel cells (PDMFCs) application. [Copyright &y& Elsevier]

Some uniquely microstructured bi/poly-metal alloys containing lesser or no noble metal have been testified to be cost-effective catalysts suitable for solvolytic dehydrogenation of ammonia borane, which expects the intensive study on their morphological engineering and synergistic mechanism. To this, we here introduce a facile and flexible fabricating protocol, i.e. stepwise wet-chemical reduction route, to purposefully modulate the orientated growth of Pd–Cu alloyed crystals via joint operation of adding suitable additives and adjusting temperature. The characterization of phase composition and evaluation of catalytic ability regarding as-fabricated Pd–Cu nanocrystals with diverse morphological features (e.g. concave tetrahedron, cube, polyhedron, nanosphere, nanowire, worm-like, seaurchin-like, flower-like, etc.) demonstrates that the nanocrystals have homogeneous alloyed phase, holding significantly enhanced catalytic activity and durability. The formation of synergistic effect due to charge transfer from Cu to Pd gives rise to electron enrichment around Pd atomic nucleus, facilitating the adsorption of H to form metal-H species, thus promoting the dehydrogenation of ammonia borane. The difference of catalytic activity of the Pd–Cu nanocrystals with different shapes reveals their morphologic dependent nature, endowing the uniquely shaped bimetal nanocrystals with exceptional catalytic performance. The concave tetrahedron shaped Pd–Cu alloyed nanocrystals hold the excellent catalytic activity almost equivalent to that of noble metal Pd, catalyzing hydrolytic reaction of ammonia borane at 298 K with the apparent activation energy of 31.18 kJ/mol, and maintaining 89% of the incipient catalytic ability after 5 recycling runs. Theoretically, the suggested morphologic tuning strategy can be also applied in fabricating other bi/poly metal alloy catalysts, with great practical potential and development prospects. Image 1 • Hierarchically alloyed Pd–Cu microarchitectures with tunable shapes were fabricated. • Flexible & reliable morphology engineering tactics via wet stepwise reduction route. • Catalysis of Pd–Cu alloys was evaluated by hydrolyzing ammonia borane to release H 2. • Concave tetrahedron shaped Pd–Cu alloys have superb catalytic ability and reusability. • Formation of synergistic effect & catalytic strengthening mechanism were discussed. [ABSTRACT FROM AUTHOR]

The method proves superior to previously developed protocols, thus providing variously substituted polycyclic spirooxindoles in virtually quantitative yields with excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

This mild and general route enables the construction of functionalized 1H-indenes utilizing a visible light photoredox catalysis strategy. [ABSTRACT FROM AUTHOR]

Highly efficient electrocatalysts for oxygen evolution reaction play key roles in various energy storage/conversion devices. Promoting the reaction rates and decreasing the overpotentials of the electrocatalysts for oxygen evolution reaction are critical for their practical application. Herein, we realize the first successful synthesis of Co 2 N 0.67 with three-dimensional architecture of hierarchical meso-macroporous nanoflowers stacked by the nanoplates with polystyrene spheres as the template. The Co 2 N 0.67 nanoflowers exhibit both low overpotential (258 mV at 10 mA cm−2) and low Tafel slope (52.22 mV dec−1) as well as superior stability for oxygen evolution reaction in alkaline medium, which makes Co 2 N 0.67 nanoflowers to be one of best earth-abundant elements based electrocatalysts toward oxygen evolution reaction to date. Importantly, being different from the previous observation that the cobalt nitrides with higher nitrogen content possess lower oxygen evolution reaction electrocatalytic abilities, we find Co 2 N 0.67 exhibits higher oxygen evolution reaction activity than Co 5.47 N. The density functional theory calculations reveal that during the oxygen evolution reaction, the oxidation step from O* to OOH* on Co 2 N 0.67 and Co 5.47 N is considered as the rate-determining step, making oxygen evolution reaction to be more thermodynamically favorable on Co 2 N 0.67 than that on Co 5.47 N. Image 1 • Co 2 N 0.67 possesses 3D architecture of hierarchical meso-macroporous nanoflowers (NFWs). • Co 2 N 0.67 NFWs needs a low potential of 1.488 V vs. RHE to drive 10 mA cm−2 for OER in 1.0 M KOH. • Co 2 N 0.67 exhibits higher OER electrocatalytic activity than Co 5.47 N in alkaline solution. • DFT calculations confirm the higher thermodynamical favorability on Co 2 N 0.67 than that on Co 5.47 N. [ABSTRACT FROM AUTHOR]

The title reaction is catalyzed by K3PO4. [ABSTRACT FROM AUTHOR]

The utilization of a new perrhenate containing ionic liquid for the efficient, environmentally friendly oxidation of a broad range of aryl and alkyl sulfides to the corresponding sulfones is described. [ABSTRACT FROM AUTHOR]