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The low uniformity in properties of relaxor ferroelectric crystals is a long-standing issue in the ferroelectric community, which limits the available volume of the entire crystal boule. The aim of this study is to develop a relaxor ferroelectric crystal with improved property uniformity and excellent piezoelectricity. To this end, Pb(In 1/2 Nb 1/2 )O 3 -Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 is doped with Nd 2 O 3 (Nd-PIN-PMN-PT) to improve the crystal performance. Along the crystal boule, the piezoelectric coefficient d 33 varies from 2800 to 3500 pC N -1 , and the dielectric constant ranges from 8400 to 9800, with variations of 25% and 16%, respectively. Such high property uniformity results in over 75% available volume of the crystal boule, compared to 30-50% for undoped crystals grown by Bridgman method. At the electric field of 1 kV cm -1 , the converse piezoelectric response is up to 4780 pm V -1 . In addition, its Curie temperature (T C ) and coercive field (E C ) are above 150 °C and 3 kV cm -1 , respectively. Compared with Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 crystal (d 33 : 1500 pC N -1 , T C : 135 °C, E C : 2.3 kV cm -1 ), the larger piezoelectricity, the higher T C and E C , and improved uniformity make Nd-PIN-PMN-PT crystals promising candidates for advanced piezoelectric applications., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The diastereo- and enantioselective construction of vicinal all-carbon quaternary stereocenters is a formidable task. We here report a synergistic bimetallic catalysis via a chiral N,N'-dioxide-europium (Eu) complex and a phosphoramidite-iridium (Ir) catalyst for the asymmetric allylation of oxindole derivatives by using challenging trisubstituted allylic esters. The allylated products bearing vicinal all-carbon quaternary stereocenters were obtained with good diastereoselectivities (up to 20 : 1 dr) and excellent enantioselectivities (up to 99 % ee). Control experiments showed that the complementary diastereomers of the products were not accessible by the change of the stereochemistry of the chiral N,N'-dioxide ligand., (© 2022 Wiley-VCH GmbH.)

The ubiquity of sulfur-containing molecules in biologically active natural products and pharmaceuticals has long attracted synthetic chemists to develop efficient strategies towards their synthesis. The strategy of direct α-C(sp 3 )-H modification of sulfides provides a streamlining access to complex sulfur-containing molecules. Herein, we report a photoinduced chemo-, site- and stereoselective α-C(sp 3 )-H functionalization of sulfides using isatins as the photoredox reagent and coupling partner catalyzed by a chiral gallium(III)-N,N'-dioxide complex. The reaction proceeds through a verified single-electron transfer (SET) mechanism with high efficiency, excellent functional group tolerance, as well as a broad substrate scope. Importantly, this cross-coupling protocol is highly selective for the direct late-stage functionalization of methionine-related peptides, regardless of the inherent structural similarity and complexity of diverse residues., (© 2022 Wiley-VCH GmbH.)

An asymmetric allylic C-H functionalization has been developed by making use of transient chiral nucleophiles, as well as bimetallic synergistic catalysis with an achiral Pd 0 catalyst and a chiral N,N'-dioxide-Co II complex. A variety of β-ketoesters and N-Boc oxindoles coupled with allylbenzenes and aliphatic terminal alkenes were well tolerated, furnishing the desired allylic alkylation products in high yields (up to 99 %) with excellent regioselectivities and enantioselectivities (up to 99 % ee)., (© 2022 Wiley-VCH GmbH.)

An atypical guanine exchange factor, Dock2 is specifically expressed in hematopoietic cells and regulates activation and migration of immune cells through activating Ras-related C3 botulinum toxin substrate (Rac). Dock2 was shown to be critical in the development of various inflammatory diseases, including allergic diseases, HIV infection, and graft rejection in organ transplantation. DOCK2 mutation in infants was recently identified to be associated with T and B cell combined immunodeficiency. Furthermore, Dock2 is involved in host protection during enteric bacterial infection and is also associated with the proliferation of cancer cells. It was also shown that patients with digestive tract cancer had high frequency mutation of DOCK2. This review summarizes the latest research progresses on the role of Dock2 for the development of various inflammatory diseases and cancers, and discusses the potential application of Dock2 modulators for patient treatment., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A biomimetic total synthesis of racemic homodimericin A was achieved in seven steps, including two cascade reactions. Aqueous buffer solutions are found to help both the oxidative dimerization cascade and the intramolecular Diels-Alder cascade. This synthetic sequence validates key steps in the biogenetic proposal of homodimericin A., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highly efficient kinetic resolution of 2H-azirines by an asymmetric imine amidation was achieved in the presence of a chiral N,N'-dioxide/Sc(III) complex, thus providing a promising method to obtain the enantioenriched 2H-azirine derivatives and protecting-group free aziridines at the same time. It is rare to find an example of N1 of an oxindole participating in a reaction over C3. Moreover, chiral 2H-azirines were stereospecifically transformed into an unprotected aziridine and α-amino ketone., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The asymmetric propargyl Claisen rearrangement provides a convenient entry to chiral allene motifs. Herein, we describe the development of a kinetic resolution and asymmetric rearrangement of racemic propargyl vinyl ethers. This transformation afforded chiral allene products along with the enantiomerically enriched substrate in good yields with excellent diastereo- and enantioselectivity. The complete chirality transfer and facially selective rearrangement enabled the simultaneous construction of an axially chiral allenic unit and a quaternary carbon stereocenter., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highly efficient catalytic asymmetric Claisen rearrangements of O-propargyl β-ketoesters and O-allyl β-ketoesters have been accomplished under mild reaction conditions. In the presence of the chiral N,N'-dioxide/Ni(II) complex, a wide range of allenyl/allyl-substituted all-carbon quaternary β-ketoesters was obtained in generally good yield (up to 99%) and high diastereoselectivity (up to 99:1 d.r.) with excellent enantioselectivity (up to 99% ee)., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)